Selfish node detection method, device, equipment and storage medium in social perception network

Abstract

The present application discloses a method, device, equipment and storage medium for detecting selfish nodes in a social perception network, and relates to the field of data processing technology. The present application discloses a method for detecting selfish nodes in a social perception network, including: obtaining each node in the social perception network, judging whether the node is a selfish node according to the residual energy and the rate of rejecting received messages of each node, and obtaining a first judgment result; when the first judgment result is that the node is not the selfish node, judging whether the node is a selfish node by calculating the social trust of the node, and obtaining a second judgment result; when the second judgment result is that the node is not the selfish node, checking whether the node forwards the message after receiving the message and checking whether the node discards the message to judge whether the node is a selfish node. The present application can detect selfish nodes in a social perception network and improve data transmission performance.

Description

Technical Field

[0001] The present application relates to the field of data processing technology, and in particular to a selfish node detection method, device, equipment and storage medium in a social perception network. Background Art

[0002] There is no end-to-end transmission path in social perception networks. The successful transmission of data mainly depends on the mutual cooperation between nodes. Due to their limited resources and the strength of social relations, nodes will show a certain degree of individual selfishness and social selfishness. The selfish behavior of nodes will seriously affect the network performance. In general, the coarse positioning method is used to determine the range of selfish nodes, and then the fine positioning method is used to judge the selfish nodes. The accuracy of this selfish node judgment method is insufficient, which may lead to the omission of selfish nodes and affect the credibility of selfish node judgment.

[0003] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0004] The main purpose of this application is to provide a method, device, equipment and storage medium for detecting selfish nodes in a social perception network, aiming to solve the technical problem of missing selfish nodes in a social perception network.

[0005] To achieve the above objectives, the present application proposes a method for detecting selfish nodes in a social perception network, the method comprising:

[0006] Obtain each node in the social perception network, determine whether the node is a selfish node according to the residual energy and the rate of refusing to receive messages of each node, and obtain a first determination result;

[0007] When the first judgment result is that the node is not the selfish node, determining whether the node is a selfish node by calculating the social trust of the node, thereby obtaining a second judgment result;

[0008] When the second judgment result is that the node is not the selfish node, it is determined whether the node is a selfish node by checking whether the node forwards the message after receiving the message and checking whether the node discards the message.

[0009] In one embodiment, the step of judging whether a node is a selfish node according to the residual energy and the rate of refusing to receive messages of the node comprises:

[0010] If the remaining energy of a node is less than the minimum energy required to forward a message, the node is marked as a selfish node;

[0011] If the remaining energy of the node is greater than the minimum energy required to forward the message, the node's message rejection rate is obtained based on the total number of messages that the node refuses to receive and the total number of message forwarding requests received by the node;

[0012] If the rate of a node refusing to receive messages is greater than a minimum threshold of the rate of a node refusing to receive messages, the node is marked as a selfish node.

[0013] In one embodiment, the step of determining whether the node is a selfish node by calculating the social trust of the node includes:

[0014] By calculating the individual and social benefits of nodes sending messages, we can get the comprehensive benefits of nodes sending messages.

[0015] Conduct supervision and analysis on the individual benefits, social benefits and comprehensive benefits of the node forwarding messages, identify possible selfish behaviors of the node, and determine the social trust of the node;

[0016] According to the social trust of the node, it is determined whether the node is an individual selfish node or a social selfish node, and the node is marked as a selfish node.

[0017] In one embodiment, the step of calculating the individual benefit and social benefit of the node sending the message to obtain the comprehensive benefit of the node sending the message includes:

[0018] According to the source node information of the message, the expected delay time of the message from the node to the destination node and the life cycle of the message, the individual benefit of the node forwarding the message is obtained;

[0019] Obtaining the social benefit of the node forwarding the message according to the social relationship between the node and the source node of the message and the social relationship between the node and the sender node of the message;

[0020] Obtaining the degree of social awareness of the node according to the individual benefit of the node forwarding the message and the social benefit of the node forwarding the message;

[0021] According to the individual benefit of the node forwarding the message, the social benefit of the node forwarding the message and the degree of social awareness of the node, the comprehensive benefit of the node forwarding the message is obtained.

[0022] In one embodiment, the social trust includes individual selfish trust, social selfish trust and normal trust; the step of supervising and analyzing the individual benefit, social benefit and comprehensive benefit of the node forwarding the message, identifying the selfish behavior that may occur in the node, and determining the social trust of the node includes:

[0023] According to the comprehensive benefits of forwarding messages, the normal trust level at the first moment is obtained;

[0024] According to the individual benefit of forwarding the message, the individual selfish trust at the first moment is obtained;

[0025] According to the social benefits of forwarding the message, the social selfish trust at the first moment is obtained;

[0026] According to the normal trust degree of the node at the second moment and the normal trust degree of the node at the first moment, an updated normal trust degree at the first moment is obtained;

[0027] According to the individual selfish trust of the node at the second moment and the individual selfish trust of the node at the first moment, the updated individual selfish trust at the first moment is obtained;

[0028] According to the social selfish trust of the node at the second moment and the social selfish trust of the node at the first moment, the updated social selfish trust at the first moment is obtained;

[0029] During the iteration cycle, the normal trust, individual selfish trust, and social selfish trust obtained at the current moment are replaced and updated;

[0030] The normal trust, individual selfish trust and social selfish trust corresponding to the end time point of the iteration are taken as the updated normal trust, individual selfish trust and social selfish trust.

[0031] In one embodiment, the step of determining whether the node is an individual selfish node or a social selfish node according to the social trust of the node includes:

[0032] If the normal trust of the node is greater than the sum of the node's individual selfish trust and the node's social selfish trust, it means that the node is neither an individual selfish node nor a social selfish node;

[0033] If the individual selfish trust of the node is greater than the normal trust of the node and the individual selfish trust of the node is greater than the social selfish trust of the node, the node is determined to be an individual selfish node;

[0034] If the social selfish trust of the node is greater than the normal trust of the node and the social selfish trust of the node is greater than the individual selfish trust of the node, the node is determined to be a social selfish node.

[0035] In one embodiment, the step of checking whether the node forwards the message after receiving the message and checking whether the node discards the message to determine whether the node is a selfish node includes:

[0036] Judging whether the node has message forwarding behavior according to the message receiving record table of the target node, if the node has message forwarding behavior, judging the node as a non-selfish node;

[0037] If the node does not have any message forwarding behavior, check the encounter record table of the target node to determine whether the node and the target node meet;

[0038] If there is an encounter record between the node and the target node, check the message sending record table of the sending node to determine whether the node encounter time is earlier than the message sending time;

[0039] If the node encounter time is later than the message sending time, determine whether the remaining survival time of the message is less than the difference between the encounter time and the sending time or whether the remaining space of the node is less than the minimum threshold of the cache space required to forward the message.

[0040] If any of the above items is not satisfied, determining whether the difference between the encounter time and the message sending time is greater than a maximum time threshold of the encounter time;

[0041] If the difference between the encounter time and the message sending time is less than the maximum time threshold of the encounter time, the node is determined to be a selfish node.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a selfish node detection device in a social perception network, the selfish node detection device in the social perception network comprising: a node subjective forwarding willingness detection module, used to obtain each node in the social perception network, and judge whether the node is a selfish node according to the residual energy and the rejection rate of receiving messages of each node, and obtain a first judgment result;

[0043] A node social trust detection module, configured to, when the first judgment result is that the node is not the selfish node, determine whether the node is a selfish node by calculating the social trust of the node, and obtain a second judgment result;

[0044] The message confirmation feedback detection module is used to check whether the node has message forwarding behavior after receiving the message and whether the node has message discarding behavior to determine whether the node is a selfish node when the second judgment result is that the node is not the selfish node.

[0045] In addition, to achieve the above-mentioned purpose, the present application also proposes a selfish node detection device in a social perception network, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the selfish node detection method in a social perception network as described above.

[0046] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the selfish node detection method in the social perception network as described above are implemented.

[0047] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the steps of the selfish node detection method in the social perception network as described above.

[0048] This application proposes a method for detecting selfish nodes in a social perception network, which has at least the following technical effects:

[0049] By obtaining each node in the social perception network, judging whether the node is a selfish node according to the residual energy and the rate of refusing to receive messages of each node; if the judgment result is that the node is not a selfish node, then judging whether the node is a selfish node by calculating the social trust of the node; if the judgment result is that the node is not a selfish node, judging whether the node is a selfish node by checking whether there is a message forwarding behavior after the node receives the message and checking whether the node has a message discarding behavior. Since this method uses three different judgment methods in sequence to judge whether a node in the social perception network is a selfish node, after any step of judging that the node is a selfish node, the node is added to the selfish node list, and the nodes in the selfish node list are removed from the social perception network. In the process of message forwarding, the message is no longer forwarded through the nodes in the selfish node list, which solves the technical problem of missing selfish nodes in the social perception network. Compared with the prior art, the accuracy of selfish node detection in the social perception network is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0051] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0052] Figure 1 A flowchart of Embodiment 1 of the method for detecting selfish nodes in a social perception network provided in the present application;

[0053] Figure 2A flowchart of a node subjective forwarding willingness detection mechanism provided in Example 1 of the present application;

[0054] Figure 3 A graph showing the effect of the order of node forwarding messages on its benefits provided in Example 1 of the present application;

[0055] Figure 4 A flowchart of a node social trust detection mechanism provided in Example 1 of the present application;

[0056] Figure 5 A flow chart of a confirmation feedback mechanism for a message provided in Example 1 of the present application;

[0057] Figure 6 A schematic diagram of a brief process of a method for detecting selfish nodes in a social perception network provided in Example 1 of the present application;

[0058] Figure 7 This is a schematic diagram of the module structure of a selfish node detection device in a social perception network according to an embodiment of the present application;

[0059] Figure 8 Schematic diagram of the device structure of the hardware operating environment involved in the selfish node detection method in the social perception network in the embodiment of the present application.

[0060] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0061] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0062] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0063] The main solutions of the embodiments of this application are:

[0064] The execution subject of the method of this embodiment can be a computing service device with social perception network data forwarding, data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc.; it can also be the above-mentioned social perception network data forwarding device with the same or similar functions. This embodiment and the following embodiments will be described by taking the social perception network data forwarding device as an example.

[0065] Since there is no end-to-end transmission path in social perception networks, the successful transmission of data mainly depends on the mutual cooperation between nodes. Due to their limited resources and the strength of social relations, nodes will show a certain degree of individual selfishness and social selfishness. The selfish behavior of nodes will seriously affect network performance.

[0066] The present application provides a solution to determine the selfishness of a node. If a node is determined to be a selfish node, the node is added to a selfish node list, and the nodes in the selfish node list are removed from the social perception network. In the process of message forwarding, messages are no longer forwarded through the nodes in the selfish node list. This solves the technical problem of the existence of selfish nodes in the social perception network, which leads to reduced network performance. Compared with the existing technology, this effectively improves the efficiency of data transmission in the social perception network.

[0067] Based on this, the embodiment of the present application provides a method for detecting selfish nodes in a social perception network, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the selfish node detection method in the social perception network of the present application.

[0068] In this embodiment, the method for detecting selfish nodes in a social perception network includes steps S10 to S30:

[0069] Step S10, obtaining each node in the social perception network, judging whether the node is a selfish node according to the residual energy and the rate of rejecting received messages of each node, and obtaining a first judgment result;

[0070] It should be noted that the residual energy of a node is a property of the node, and the residual energy of the node can be directly obtained through the node information. The residual energy of the node can be used to analyze the energy limitation of the node. The energy limitation of the node refers to the selfish behavior of the node due to energy limitation. Nodes in the network consume energy when forwarding messages. The more sufficient the residual energy of the node, the more capable the node is to forward messages. If the residual energy of the node is not sufficient, the node may be unwilling to forward messages due to its own energy deficiency. Therefore, the selfishness of the node can be judged by comparing the residual energy of the node with the minimum energy required to forward messages in the network.

[0071] In addition, it should be noted that the rejection rate mainly refers to the degree to which a node refuses to receive messages, which is the ratio of the total number of messages that a node refuses to receive to the total number of message forwarding requests received by the node. Since the remaining cache space of a node will also affect the message forwarding of the node, when the remaining cache space of a node is temporarily insufficient, the node may refuse to receive messages. In order to prevent the node from misjudging its selfishness due to temporary insufficient cache space, the selfishness of the node is judged by calculating the rejection rate of the node and setting a certain threshold.

[0072] It is understandable that due to the limitation of node energy and cache space, a certain amount of energy will be consumed and a certain amount of cache space will be occupied during message transmission, so there is a behavior that nodes are unwilling to consume their own resources to provide message forwarding services for other nodes, showing selfishness. Therefore, step S10 can be performed to analyze the node's energy limitation and the rate of refusing to receive messages based on the node's remaining resources, thereby detecting the node's selfishness.

[0073] In a feasible implementation, step S10 may include steps A11 to A13:

[0074] Step A11, if the remaining energy of the node is less than the minimum energy required to forward the message, the node is marked as a selfish node;

[0075] It should be noted that E remain Represents the remaining energy value of the node, E min Represents the minimum energy required to forward a message in the network.

[0076] It is understandable that if E remain ≤E min , indicating that the remaining energy of the node is too low to support the forwarding of messages. The node will show selfish behavior of refusing to provide forwarding message service. At this time, the node is marked as selfish, and there is no need to consider the node's refusal to receive messages rate, because the node's insufficient energy directly leads to the node's inability to forward messages, and it will not receive messages.

[0077] Step A12, if the remaining energy of the node is greater than the minimum energy required to forward the message, the node's message rejection rate is obtained according to the total number of messages rejected by the node and the total number of message forwarding requests received by the node;

[0078] It is understandable that if E remain >E min , indicating that the remaining energy of the node is sufficient, and the node can consume a certain amount of energy to forward messages to other nodes. The node’s message rejection rate will continue to be calculated to further judge the node’s selfishness.

[0079] It should be noted that the node's message rejection rate RMR can be expressed as Formula 1:

[0080]

[0081] In the formula, Sum rej Indicates the total number of nodes that refuse to receive messages, Sum req Indicates the total number of message forwarding requests received by the node.

[0082] Step A13: if the rate of the node refusing to receive messages is greater than the minimum threshold of the rate of the node refusing to receive messages, the node is marked as a selfish node.

[0083] It should be noted that the minimum threshold for the rate of rejected messages is RMR. min It is the minimum threshold for a node to refuse to receive a message, which causes the node to be selfish. The value is set manually. Since RMR is a ratio, the range is 0-1, so RMR min The range of is also 0-1, such as 0.5 or 0.3. This embodiment does not limit the value of the message rejection rate.

[0084] It is understandable that if RMR>RMR min , indicating that the node's rejection rate of receiving messages is too high. Even if there are nodes in the network that refuse to receive messages due to insufficient remaining cache space, a high RMR indicates that the node itself is more likely to refuse to receive messages because it wants to save cache space. In this case, the node is marked as a selfish node.

[0085] In addition, it is understood that if RMR ≤ RMR min , indicating that the node is more likely to be selfish due to temporary lack of remaining cache space, and thus there is a certain behavior of refusing to receive messages, so this does not prove that the node is selfish. Therefore, when step S10 cannot identify the selfish node, step S20 will be used to conduct a more in-depth selfishness identification of the node.

[0086] In this implementation, starting from the remaining resources of the node, the node's energy limitation and the rate of refusing to receive messages are analyzed to detect the selfishness of the node and preliminarily determine the selfish nodes in the social perception network. Through the understanding and summary of this implementation, step S10 can be called a node subjective forwarding willingness detection mechanism.

[0087] For example, to help understand the implementation process of the selfish node detection method in the social perception network obtained in this embodiment in combination with the above step S10, please refer to Figure 2 , Figure 2 A flowchart of the node subjective forwarding willingness detection mechanism is provided, specifically:

[0088] When nodes meet and forward messages, they check the remaining energy of the nodes. If it does not meet E remain >E min , then the node is a selfish node. If it meets E remain >E min Then further check the node's rejection rate of received messages. If RMR>RMR min If RMR≤RMR min, it means that the selfishness of the node cannot be detected through the node subjective forwarding willingness detection mechanism, and further judgment is needed through the node social trust detection mechanism.

[0089] Step S20, when the first judgment result is that the node is not the selfish node, by calculating the social trust of the node, determining whether the node is a selfish node, and obtaining a second judgment result;

[0090] It can be understood that the selfishness of nodes can be divided into individual selfishness and social selfishness, so selfish nodes can be divided into individual selfish nodes and social selfish nodes. Individual selfish nodes will forward their local messages, and will also store and send non-local messages that have a high probability of forwarding messages to their destination nodes through the node. Social selfish nodes will forward their local messages, and will also receive or forward non-local messages from intermediate nodes according to the strength of their social relationships.

[0091] In practical applications, nodes can bring the highest individual benefits when sending local messages. For individual selfish nodes, when nodes send non-local messages, if the expected delay time for the message to be delivered to its destination node is less than the survival time of the message, the node can bring the highest individual benefits. For social selfish nodes, they will forward their local messages and also receive or forward non-local messages from intermediate nodes according to the strength of their social relationships. Therefore, the comprehensive benefit of individual selfish nodes forwarding messages is determined by their individual benefits of forwarding messages, while the comprehensive benefit of social selfish nodes is determined by their individual benefits and social benefits. The comprehensive benefit of a node forwarding a message is determined by the individual benefits, social benefits, and degree of social awareness of the node forwarding messages.

[0092] In addition, in practical applications, the social relationship between nodes in social perception networks will affect the selfishness of nodes, especially for socially selfish nodes. Apart from the reasons of resource constraints, if the social relationship between two nodes is closer, they will be more willing to cooperate with each other in message transmission. The degree of social awareness of nodes is an important factor in calculating the benefits of forwarding messages to nodes. The social relationship between nodes is analyzed by the historical information of nodes, such as the contact frequency, contact time, and their contact rules. At the same time, the social similarity of nodes will also affect the social relationship between nodes. Therefore, the social relationship between nodes is jointly determined by social pressure measurement and social similarity.

[0093] It should be noted that the social pressure measurement SPM is a new method to measure the intimacy of nodes through three characteristics: high frequency, longevity, and regularity. In other words, only when two nodes maintain frequent and regular contact in long-term contact and communication, they will be regarded as friends by each other. The social pressure measurement between node i and node j is constructed by formula 2:

[0094]

[0095] Where SPM i,j represents the social pressure measure between nodes i and j. f(t) returns the remaining time for the next encounter between the two nodes at time t. If the two nodes are connected at time t, f(t) = 0. Otherwise, f(t) = t next -t,t next It refers to the time when two nodes meet next time, and T represents the entire experimental cycle.

[0096] The social similarity socsim is measured by the number of common neighbor nodes between two nodes, which indicates the similarity between the two nodes. The social similarity between node i and node j is constructed by formula 3:

[0097]

[0098] In the formula, socsim i,j represents the social similarity between node i and node j, comm i,j Indicates the number of common neighbor nodes between node i and node j, nbr i Indicates the total number of neighbor nodes of node i, nbr j Represents the total number of neighbor nodes of node j.

[0099] Since the social relationship SR between nodes is determined by the social pressure measure SPM and the social similarity socsim, according to the definitions of Formula 2 and Formula 3, the social relationship between node i and node j is constructed by Formula 4:

[0100] SR i,j =μSPM i,j +(1-μ)socsim i,j Formula 4;

[0101] In the formula, SR i,j represents the social relationship between node i and node j, μ is the SPM i,j and socsim i,j are influential weight factors, and μ∈[0,1].

[0102] It is understandable that both individual selfish nodes and social selfish nodes forward messages in descending order of their benefits, aiming to maximize their routing performance. Therefore, by analyzing the order in which nodes forward messages, we can determine the possible selfishness of the nodes. Figure 3 , Figure 3The following is a graph showing the effect of the order in which nodes forward messages on their benefits. When node i is an individual selfish node, node i will instinctively forward local messages first to obtain the highest individual benefit, and then forward non-local messages in descending order of its individual benefit. When node i is a socially selfish node, node i will forward messages in descending order of its comprehensive benefit. To calculate the comprehensive benefit of a node, the node's social perception must be calculated first. Socially selfish nodes can assign the highest benefit to non-local messages, but individual selfish nodes always assign the highest benefit to local messages. Therefore, the individual selfishness and social selfishness of nodes can be distinguished by the properties of the node forwarding messages.

[0103] It should be noted that the social trust of a node is divided into normal trust, individual selfish trust and social selfish trust. The normal trust of a node refers to the possibility of having selfless behavior, the individual selfish trust of a node refers to the possibility of a node being an individual selfish node, and the social selfish trust of a node refers to the possibility of a node being a social selfish node.

[0104] In addition, it should be noted that the normal trust of the node is calculated by the comprehensive benefit of the node forwarding the message, the individual selfish trust of the node is calculated by the individual benefit of the node forwarding the message, and the social selfish trust of the node is calculated by the social benefit of the node forwarding the message. The selfishness of the node is confirmed by comparing the calculated normal trust, individual selfish trust and social selfish trust. If the node is determined to be selfish, it is added to the selfish node list and will no longer pass through this node in subsequent message forwarding. If the selfishness of the node cannot be confirmed, the selfishness of the node will be further judged through step S30.

[0105] In this implementation, by calculating the individual benefit, comprehensive benefit and social benefit of the node forwarding the message, the normal trust, individual selfish trust and social selfish trust of the node are further calculated. By comparing the normal trust, individual selfish trust and social selfish trust of the node, the selfishness of the node is confirmed, thereby judging the selfish node in the social perception network. Through the understanding and summary of this implementation, step S20 can be called a node social trust detection mechanism.

[0106] Step S30, when the second judgment result is that the node is not the selfish node, checking whether the node forwards the message after receiving the message and checking whether the node discards the message to determine whether the node is a selfish node.

[0107] It should be noted that each node in the social perception network will maintain and update the information of encounters with other nodes. At the same time, it will also maintain and update the sending and receiving behavior information of forwarded messages. By exchanging information when nodes meet, it is possible to check whether the nodes have selfish behaviors such as discarding messages.

[0108] In addition, it should be noted that all nodes in the network maintain and update the forwarding message sending record table MST, message receiving record table MRT, and node encounter record table NMT. ​​The message sending record table stores each message m sent, the sending time T send,m , the node address receiving the message and the remaining lifetime of the message The message receiving record table stores each received message m and the node address that sent the message. The node encounter record table stores the addresses of the two encountering nodes and the time T of their most recent encounter. meet , their remaining cache space B remain .

[0109] In actual applications, when node a sends message m to node b, the meeting information of the two nodes and the forwarded message information will be recorded in the corresponding table. If node a encounters node c after sending m, the information in the message sending record table, message receiving record table, and node meeting record table will be exchanged at this time, and the selfishness of node b will be judged through the shared information. If the node is judged to be selfish, it will be added to the selfish node list, and will no longer pass through this node in subsequent message forwarding. If it cannot be determined that the node is a selfish node, and the experimental cycle has not ended, the nodes will meet and forward messages, and the selfishness of the node needs to be re-judged from step S10.

[0110] In this implementation, the selfishness of the node is confirmed by comparing the information in the message sending record table, message receiving record table and node encounter record table maintained by the nodes, thereby determining the selfish nodes in the social perception network. Through the understanding and summary of this implementation, step S30 can be called a message confirmation feedback mechanism.

[0111] This embodiment provides a method for detecting selfish nodes in a social perception network, which judges the selfishness of a node through a node subjective forwarding willingness detection mechanism, a node social trust detection mechanism, and a message confirmation feedback mechanism. If a node is judged to be a selfish node, the selfish node is no longer used for message forwarding during the message forwarding process, thereby effectively improving the message forwarding efficiency of the social perception network.

[0112] In a feasible implementation, step S20 may include steps S21 to S23:

[0113] Step S21, calculating the individual benefit and social benefit of the node sending the message, and obtaining the comprehensive benefit of the node sending the message;

[0114] It can be understood that to calculate the comprehensive benefits of a node sending information, it is necessary to calculate the individual benefits of the node sending messages and the social benefits of the node sending messages in sequence, and then calculate the node's social awareness level through the individual benefits of the node sending messages and the social benefits of the node sending messages. The comprehensive benefits of the node sending messages are calculated using the individual benefits of the node sending messages, the social benefits of the node sending messages, and the node's social awareness level.

[0115] The way to calculate the individual benefit of a node sending information is as follows: based on the source node information of the message, the expected delay time for the message to be transmitted from the node to the destination node, and the life cycle of the message, the individual benefit of the node forwarding the message is constructed by formula 5:

[0116]

[0117] In the formula, IE i (m) represents the individual benefit of node i forwarding message m, src(m) represents the source node of m, T i,des(m) represents the expected delay time for m to be transmitted from node i to its destination node, TTL represents the lifetime of m, and the individual benefit IE of the node sending the message i (m)∈[0,1].

[0118] The way to calculate the social benefit of a node sending information is as follows: based on the social relationship between the node and the source node of the message and the social relationship between the node and the sender node of the message, the social benefit of the node forwarding the message is constructed by formula 6:

[0119]

[0120] Where, SE i (m) represents the social benefit of node i forwarding message m, SR i,src(m) represents the social relationship between source nodes i and m, SR i,j represents the social relationship between node i and the sender node j that sends m to i. And SE i (m)∈[0,1].

[0121] The method of calculating the degree of social awareness of a node is as follows: according to the individual benefit of the node forwarding a message and the social benefit of the node forwarding a message, the degree of social awareness of the node is obtained by formula 7:

[0122]

[0123] In the formula, δ irepresents the degree of social awareness of node i, SE i (m) represents the social benefit of message m to i, IE i (m) represents the individual benefit of m to i, and δ i ∈(0,0.5]. It can be seen from the formula that when node i receives information transmitted by other nodes with close social ties and forwards it, the social awareness of node i will be improved.

[0124] The method of calculating the comprehensive benefit of a node sending information is as follows: according to the individual benefit of the node forwarding the message, the social benefit of the node forwarding the message and the degree of social awareness of the node, the comprehensive benefit of the node forwarding the message is obtained by formula eight:

[0125] CE i (m,δ i )=(1-δ i )*IE i (m)+δ i *SE i (m) Formula 8;

[0126] Where, CE i (m,δ i ) represents the comprehensive benefit of node i forwarding message m, IE i (m) represents the individual benefit of message m to node i, SE i (m) represents the social benefit of message m to node i, represents the degree of social awareness of node i, and δ i ∈(0,0.5]. When δ i = 0, indicating that node i is an individual selfish node. i =0.5, indicating that the message m is equally important to the individual benefit and social benefit of node i.

[0127] Step S22, supervise and analyze the individual benefits, social benefits, and comprehensive benefits of the node forwarding messages, identify possible selfish behaviors of the node, and determine the social trust of the node;

[0128] It should be noted that the social trust includes individual selfish trust, social selfish trust and normal trust;

[0129] According to the comprehensive benefits of forwarding messages, the normal trust level at the first moment is constructed by Formula 9:

[0130] NT i (t) = 1-CE i (m,δ i )Formula 9;

[0131] In the formula, NT i(t) represents the normal trust of node i at time t, CE i (m,δ i ) represents the comprehensive benefit of node i forwarding message m.

[0132] According to the individual benefit of forwarding the message, the individual selfish trust at the first moment is constructed by Formula 10:

[0133] IST i (t) = IE i (m) Formula 10;

[0134] Where, IST i (t) represents the individual selfish trust of node i at time t, IE i (m) represents the individual benefit of node i forwarding message m.

[0135] According to the social benefits of forwarding messages, the social selfish trust at the first moment is constructed by Formula 11:

[0136] SST i (t) = SE i (m) Formula 11;

[0137] Where SST i (t) represents the social selfish trust of node i at time t, SE i (m) represents the social benefit of node i forwarding message m.

[0138] According to the normal trust degree of the node at the second moment and the normal trust degree at the first moment, the updated normal trust degree at the first moment is constructed by formula 12:

[0139]

[0140] In the formula, NT i (t) represents the normal trust of node i at time t, NT i (t-Δt) represents the normal trust of node i at time t-Δt.

[0141] According to the individual selfish trust of the node at the second moment and the individual selfish trust at the first moment, the updated individual selfish trust at the first moment is constructed by formula 13:

[0142]

[0143] Where, IST i (t) represents the individual selfish trust of node i at time t, IST i (t-Δt) represents the individual selfish trust of node i at time t-Δt.

[0144] According to the social selfish trust of the node at the second moment and the social selfish trust of the node at the first moment, the updated social selfish trust at the first moment is constructed by formula 14:

[0145]

[0146] Where SST i (t) represents the social selfish trust of node i at time t, SST i (t-Δt) represents the social selfish trust of node i at time t-Δt.

[0147] During the iteration cycle, the normal trust, individual selfish trust, and social selfish trust obtained at the current moment are replaced and updated;

[0148] The normal trust, individual selfish trust and social selfish trust corresponding to the end time point of the iteration are taken as the updated normal trust, individual selfish trust and social selfish trust.

[0149] Step S23: judging whether the node is an individual selfish node or a social selfish node according to the social trust of the node, and marking the node as a selfish node.

[0150] If the normal trust of the node is greater than the sum of the node's individual selfish trust and the node's social selfish trust, it means that the node is neither an individual selfish node nor a social selfish node;

[0151] It is understandable that if NT is met i >IST i +SST i , indicating that node i is more likely not to be a selfish node, excluding individual selfishness and social selfishness, and will continue to make a deeper judgment on node i through the message confirmation feedback mechanism. Otherwise, proceed to the next step to judge the selfishness of the node.

[0152] If the individual selfish trust of the node is greater than the normal trust of the node and the individual selfish trust of the node is greater than the social selfish trust of the node, the node is determined to be an individual selfish node;

[0153] It is understandable that if IST is met i >NT i And IST i >SST i , indicating that node i is an individual selfish node, the node is marked as selfish. Otherwise, proceed to the next step to judge the selfishness of the node.

[0154] If the social selfish trust of the node is greater than the normal trust of the node and the social selfish trust of the node is greater than the individual selfish trust of the node, the node is determined to be a social selfish node.

[0155] It is understandable that if SST is met i >NT i And SST i >IST i , indicating that node i is a socially selfish node, the node is marked as selfish. Otherwise, the confirmation feedback detection mechanism of the message will continue to make a deeper judgment on node i.

[0156] For example, to help understand the implementation process of the selfish node detection method in the social perception network obtained in this embodiment in combination with the above step S20, please refer to Figure 4 , Figure 4 A flowchart of the node social trust detection mechanism is provided, specifically:

[0157] When nodes meet and forward messages, the normal trust NT, individual selfish trust IST and social selfish trust SST of the nodes are calculated. If NT>IST+SST is satisfied, the selfishness of the node cannot be judged, and further judgment is required through the confirmation feedback detection mechanism of the message. If NT>IST+SST is not satisfied, continue to judge whether IST>NT and IST>SST are satisfied. If satisfied, it means that the node is an individual selfish node. If not satisfied, judge whether SST>NT and SST>IST are satisfied. If satisfied, it means that the node is an individual selfish node. If not satisfied, it means that the selfishness of the node cannot be judged, and further judgment is required through the confirmation feedback detection mechanism of the message.

[0158] In a feasible implementation, step S30 may include steps S31 to S36:

[0159] Step S31, judging whether the node has message forwarding behavior according to the message receiving record table of the target node, and if the node has message forwarding behavior, judging the node as a non-selfish node;

[0160] It is understandable that if the slave node's message reception record table MRT c In the figure, we checked that node c received the confirmation of message m forwarded from node b, which means that node b successfully forwarded m after receiving it, and there was no discarding behavior, indicating that the node is not selfish.

[0161] Step S32, if the node does not have message forwarding behavior, check the encounter record table of the target node to determine whether the node and the target node meet;

[0162] It can be understood that if the message receiving record table MRT from node c c If no confirmation is found that node c has received the message m forwarded from node b, then check the node encounter record table NMT of node c. c Check whether c has met node b. If not, it means that node b has not encountered node c after receiving m. At this time, it cannot be determined whether node b is a selfish node.

[0163] Step S33, if there is an encounter record between the node and the target node, check the message sending record table of the sending node to determine whether the node encounter time is earlier than the message sending time;

[0164] It is understandable that if there is an encounter, combined with the message sending record table MST of node a a Check the last time nodes b and c met Is it faster than the time it takes for node a to send message m? If yes, it means that when node b meets node c, node b has not received message m from node a, and it is impossible to determine whether node b is a selfish node.

[0165] Step S34, if the node encounter time is later than the message sending time, determine whether the remaining survival time of the message is less than the difference between the encounter time and the sending time or whether the remaining space of the node is less than the minimum threshold of the cache space required for forwarding the message.

[0166] It is understandable that checking the remaining survival time of m at this time Less than the time when nodes b and c meet The time when a message is sent to node a Or check the remaining cache space of node b Less than the minimum threshold B of the buffer space required to forward messages min Is it true? If so, it means that the message m has expired or node b has discarded the message due to temporary insufficient cache. At this time, it cannot be determined whether node b is a selfish node.

[0167] Step S35: If any one of the items is not satisfied, determine whether the difference between the encounter time and the message sending time is greater than the maximum time threshold of the encounter time;

[0168] It is understandable that if the judgment result of step S34 is that none of the above is true, the time when nodes b and c meet is compared. The time when node a sends m Is the difference greater than the maximum time threshold T max, used to check whether it takes a long time for node b to meet node c after receiving m. If so, it means that node b is very likely to forward m to other nodes. At this time, it cannot be judged whether the node is selfish;

[0169] Step S36: If the difference between the encounter time and the message sending time is less than the maximum time threshold of the encounter time, the node is determined to be a selfish node.

[0170] For example, to help understand the implementation process of the selfish node detection method in the social perception network obtained in this embodiment in combination with the above step S30, please refer to Figure 5 , Figure 5 A message confirmation feedback mechanism flow chart is provided, specifically:

[0171] After node a sends message m to node b, it encounters node c. It first checks node c's MRT to confirm whether c has received m. If it has, it means node b is not selfish in forwarding the message this time. If it has not, it further checks node c's NMT to see if it has met node b before. If not, it means node b is not selfish in forwarding the message this time. If they have met, it further determines the last time node b and c met. Is it faster than the time it takes for node a to send message m? If it is earlier, it means that node b is not selfish in forwarding the message this time. If it is later, then the remaining lifetime of m is Less than the time when nodes b and c meet The time when a message is sent to node a Or check the remaining cache space of node b Less than the minimum threshold B of the buffer space required to forward messages min Is it true? If true, it means that node b is not selfish in forwarding the message this time. If not true, it determines the time when nodes b and c meet. The time when node a sends m Is the difference greater than the maximum time threshold T max If it is greater than, it means that node b is not selfish in forwarding the message this time. If it is not satisfied, it means that node b is a selfish node.

[0172] For example, to help understand the implementation process of the selfish node detection method in the social perception network obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 6 , Figure 6 A brief flowchart of a selfish node detection method in a social perception network is provided. Specifically:

[0173] If nodes meet and forward messages, the node's subjective forwarding willingness detection mechanism is used to judge the selfishness of the node. The node's subjective forwarding willingness detection mechanism is to obtain each node in the social perception network, and judge whether the node is a selfish node according to the residual energy and the rate of rejection of receiving messages of each node, and obtain the first judgment result. If the node's subjective forwarding willingness detection mechanism confirms that the node is a selfish node, the node is added to the selfish list, and the node will no longer be passed through in the subsequent message forwarding process.

[0174] If the node subjective forwarding willingness detection mechanism cannot confirm that the node is a selfish node, the node social trust detection mechanism is used to determine the selfishness of the node. The node social trust detection mechanism is that when the first judgment result is that the node is not the selfish node, the social trust of the node is calculated to determine whether the node is a selfish node, and a second judgment result is obtained. If the node social trust detection mechanism confirms that the node is a selfish node, the node is added to the selfish list, and the node is no longer passed in the subsequent message forwarding process.

[0175] If the node social trust detection mechanism cannot confirm that the node is a selfish node, the node's message confirmation feedback mechanism is used to determine the selfishness of the node. The node's message confirmation feedback mechanism is to check whether the node forwards the message after receiving the message and whether the node discards the message to determine whether the node is a selfish node when the second judgment result is that the node is not the selfish node. If the node's message confirmation feedback mechanism confirms that the node is a selfish node, the node is added to the selfish list, and the node is no longer passed in the subsequent message forwarding process.

[0176] If the node's message confirmation feedback mechanism is unable to confirm that the node is a selfish node, before the end of the experimental cycle, when nodes meet and forward messages, they need to use an algorithm to detect whether the intermediate node is a selfish node.

[0177] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the selfish node detection method in the social perception network of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0178] This application also provides a selfish node detection device in a social perception network, please refer to Figure 7 , the selfish node detection device in the social perception network includes:

[0179] The node subjective forwarding willingness detection module 10 is used to obtain each node in the social perception network, determine whether the node is a selfish node according to the remaining energy and the rate of refusing to receive messages of each node, and obtain a first judgment result;

[0180] A node social trust detection module 20, configured to, when the first judgment result is that the node is not the selfish node, determine whether the node is a selfish node by calculating the social trust of the node, and obtain a second judgment result;

[0181] The message confirmation feedback detection module 30 is used to determine whether the node is a selfish node by checking whether the node forwards the message after receiving the message and whether the node discards the message when the second judgment result is that the node is not a selfish node.

[0182] The selfish node detection device in the social perception network provided by the present application adopts the selfish node detection method in the social perception network in the above embodiment, which can solve the technical problem that the selfish behavior of the node will seriously affect the network performance. Compared with the prior art, the beneficial effects of the selfish node detection device in the social perception network provided by the present application are the same as the beneficial effects of the selfish node detection method in the social perception network provided by the above embodiment, and the other technical features of the selfish node detection device in the social perception network are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0183] The present application provides a selfish node detection device in a social perception network, and the selfish node detection device in the social perception network includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the selfish node detection method in the social perception network in the above-mentioned embodiment 1.

[0184] Reference below Figure 8 , which shows a schematic diagram of the structure of a selfish node detection device in a social perception network suitable for implementing the embodiment of the present application. The selfish node detection device in the social perception network in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 8 The selfish node detection device in the social perception network shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0185] like Figure 8As shown, the selfish node detection device in the social perception network may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the selfish node detection device in the social perception network are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the selfish node detection device in the social perception network to communicate wirelessly or wired with other devices to exchange data. Although the selfish node detection device in the social perception network with various systems is shown in the figure, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0186] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0187] The selfish node detection device in the social perception network provided by the present application adopts the selfish node detection method in the social perception network in the above embodiment, which can solve the technical problem that the selfish behavior of the node will seriously affect the network performance. Compared with the prior art, the beneficial effects of the selfish node detection device in the social perception network provided by the present application are the same as the beneficial effects of the selfish node detection method in the social perception network provided by the above embodiment, and the other technical features of the selfish node detection device in the social perception network are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0188] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0189] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0190] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the selfish node detection method in the social-aware network in the above-mentioned embodiment.

[0191] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0192] The computer-readable storage medium may be included in a selfish node detection device in a social perception network; or may exist independently without being assembled into a selfish node detection device in a social perception network.

[0193] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by a selfish node detection device in a social perception network, the selfish node detection device in the social perception network: obtains each node in the social perception network, determines whether the node is a selfish node according to the residual energy and the rejection rate of receiving messages of each node, and obtains a first judgment result;

[0194] When the first judgment result is that the node is not the selfish node, determining whether the node is a selfish node by calculating the social trust of the node, thereby obtaining a second judgment result;

[0195] When the second judgment result is that the node is not the selfish node, it is determined whether the node is a selfish node by checking whether the node forwards the message after receiving the message and checking whether the node discards the message.

[0196] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0197] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0198] The readable storage medium provided in this application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned selfish node detection method in the social perception network, and can solve the technical problem that the selfish behavior of nodes will seriously affect the network performance. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the selfish node detection method in the social perception network provided in the above-mentioned embodiment, and will not be repeated here.

[0199] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method for detecting selfish nodes in a social perception network as described above.

[0200] The computer program product provided by the present application can solve the technical problem that selfish behavior of nodes can seriously affect network performance. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the selfish node detection method in the social perception network provided by the above embodiment, which will not be repeated here.

[0201] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A selfish node detection method in a social perception network, characterized in that: The method includes: Obtain each node in the social perception network, determine whether the node is a selfish node according to the residual energy and the rate of refusing to receive messages of each node, and obtain a first determination result; The step of judging whether a node is a selfish node according to the remaining energy and the rate of refusing to receive messages of the node comprises: If the remaining energy of a node is less than the minimum energy required to forward a message, the node is marked as a selfish node; If the remaining energy of the node is greater than the minimum energy required to forward the message, the node's message rejection rate is obtained based on the total number of messages the node refuses to receive and the total number of message forwarding requests the node receives; If the node's message rejection rate is greater than the minimum threshold of the node's message rejection rate, the node is marked as a selfish node; When the first judgment result is that the node is not the selfish node, determining whether the node is a selfish node by calculating the social trust of the node, thereby obtaining a second judgment result; The step of determining whether the node is a selfish node by calculating the social trust of the node includes: By calculating the individual and social benefits of nodes sending messages, we can get the comprehensive benefits of nodes sending messages. Conduct supervision and analysis on the individual benefits, social benefits and comprehensive benefits of the node forwarding messages, identify possible selfish behaviors of the node, and determine the social trust of the node; According to the social trust of the node, determine whether the node is an individual selfish node or a social selfish node, and mark the node as a selfish node; The step of obtaining the comprehensive benefit of the node sending information by calculating the individual benefit and social benefit of the node sending the message comprises: According to the source node information of the message, the expected delay time of the message from the node to the destination node and the life cycle of the message, the individual benefit of the node forwarding the message is obtained; Obtaining the social benefit of the node forwarding the message according to the social relationship between the node and the source node of the message and the social relationship between the node and the sender node of the message; Obtaining the degree of social awareness of the node according to the individual benefit of the node forwarding the message and the social benefit of the node forwarding the message; Obtaining the comprehensive benefit of the node forwarding the message according to the individual benefit of the node forwarding the message, the social benefit of the node forwarding the message and the degree of social awareness of the node; The step of judging whether the node is an individual selfish node or a social selfish node according to the social trust of the node comprises: If the normal trust of the node is greater than the sum of the node's individual selfish trust and the node's social selfish trust, it means that the node is neither an individual selfish node nor a social selfish node; If the individual selfish trust of the node is greater than the normal trust of the node and the individual selfish trust of the node is greater than the social selfish trust of the node, the node is determined to be an individual selfish node; If the social selfish trust of the node is greater than the normal trust of the node and the social selfish trust of the node is greater than the individual selfish trust of the node, the node is determined to be a social selfish node; When the second judgment result is that the node is not the selfish node, checking whether the node forwards the message after receiving the message and checking whether the node discards the message to determine whether the node is a selfish node; The step of checking whether the node has a message forwarding behavior after receiving the message and checking whether the node has a message discarding behavior to determine whether the node is a selfish node includes: Judging whether the node has message forwarding behavior according to the message receiving record table of the target node, if the node has message forwarding behavior, judging the node as a non-selfish node; If the node does not have any message forwarding behavior, check the encounter record table of the target node to determine whether the node and the target node meet; If there is an encounter record between the node and the target node, check the message sending record table of the sending node to determine whether the node encounter time is earlier than the message sending time; If the node encounter time is later than the message sending time, determine whether the remaining survival time of the message is less than the difference between the encounter time and the sending time or whether the remaining space of the node is less than the minimum threshold of the cache space required to forward the message. If any of the above items is not satisfied, determining whether the difference between the encounter time and the message sending time is greater than a maximum time threshold of the encounter time; If the difference between the encounter time and the message sending time is less than the maximum time threshold of the encounter time, the node is determined to be a selfish node.

2. The method according to claim 1, characterized in that The social trust includes individual selfish trust, social selfish trust and normal trust; the steps of supervising and analyzing the individual benefit, social benefit and comprehensive benefit of the node forwarding messages, identifying the possible selfish behavior of the node, and determining the social trust of the node include: According to the comprehensive benefits of forwarding messages, the normal trust level at the first moment is obtained; According to the individual benefit of forwarding the message, the individual selfish trust at the first moment is obtained; According to the social benefits of forwarding the message, the social selfish trust at the first moment is obtained; According to the normal trust degree of the node at the second moment and the normal trust degree of the node at the first moment, an updated normal trust degree at the first moment is obtained; According to the individual selfish trust of the node at the second moment and the individual selfish trust of the node at the first moment, the updated individual selfish trust at the first moment is obtained; According to the social selfish trust of the node at the second moment and the social selfish trust of the node at the first moment, the updated social selfish trust at the first moment is obtained; During the iteration cycle, the normal trust, individual selfish trust, and social selfish trust obtained at the current moment are replaced and updated; The normal trust, individual selfish trust and social selfish trust corresponding to the end time point of the iteration are taken as the updated normal trust, individual selfish trust and social selfish trust.

3. A selfish node detection device in a social perception network, used to adopt the selfish node detection method in a social perception network as described in any one of claims 1 or 2, characterized in that: The device comprises: The node subjective forwarding willingness detection module is used to obtain each node in the social perception network, judge whether the node is a selfish node according to the residual energy and the rate of refusing to receive messages of each node, and obtain a first judgment result; A node social trust detection module, configured to, when the first judgment result is that the node is not the selfish node, determine whether the node is a selfish node by calculating the social trust of the node, and obtain a second judgment result; The message confirmation feedback detection module is used to check whether the node has message forwarding behavior after receiving the message and whether the node has message discarding behavior to determine whether the node is a selfish node when the second judgment result is that the node is not the selfish node.

4. A selfish node detection device in a social perception network, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the method for detecting selfish nodes in a social perception network according to any one of claims 1 or 2.

5. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the selfish node detection method in a social perception network as described in any one of claims 1 or 2 are implemented.

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