Opportunistic network routing method based on adaptive cluster division

Abstract

The invention discloses an opportunity network routing method based on adaptive cluster division, and belongs to the field of opportunity networks. The problem that a traditional opportunity network routing method cannot enable the network to obtain good performance is solved. The method comprises the following steps: firstly, setting an updating period T of a global active node, and determining the global active node according to a global active node determining method; secondly, the network is clustered according to the geographic area, a cluster head node is selected for each cluster, and when the nodes generate messages, the total number of copies of the messages in the network is limited by initially setting the number of copies of the messages; and when a message needs to be forwarded in the node, selecting a proper node as a relay node according to whether a cluster head node, a global active node and the like exist in the selectable nodes, and completing message forwarding. And finally, when the updating period T of the global active node is reached, the initial copy number of the message in the updating period of the next global active node is adjusted according to the performance such as the delivery rate and the discarding rate of the network. The present invention is mainly used in routing communication.

Description

Technical Field

[0001] The invention belongs to the field of opportunistic networks, and in particular relates to an opportunistic network routing method based on adaptive cluster division. Background Art

[0002] Opportunistic network is a new type of network architecture. In opportunistic network, there is no complete transmission path between source node and destination node. Network communication is usually achieved by using the encounter opportunities brought by node movement. Compared with traditional networks, opportunistic network has the characteristics of node mobility, intermittent connectivity, and limited resources. In order to overcome these network characteristics, opportunistic network adopts "store-carry-forward" routing method for message transmission. In opportunistic network, due to the characteristics of opportunistic network, the message delivery rate and discard rate cannot achieve good performance. Therefore, how to design efficient routing method so that the network can achieve better performance is an important research content in opportunistic network.

[0003] Currently, typical routing algorithms in opportunistic networks include Epidemic routing algorithm, Spray and Wait routing algorithm, etc.

[0004] The Epidemic routing algorithm adopts a flooding strategy. It forwards messages by distributing a copy of the message to each node it contacts, and each node distributes its copy to each adjacent node. This process continues until a copy of the message is delivered to the destination node. This routing algorithm can achieve a good delivery rate, but the algorithm continuously copies messages during the message transmission process, which will quickly exhaust the limited resources in the network, and thus fail to effectively utilize the resources in the network, reducing network performance.

[0005] The Spray and Wait routing algorithm limits the number of copies in the network through certain strategies. In the Spray phase, the source node and the relay node forward a certain number of messages to the neighboring nodes. In the Wait phase, each node carrying a copy of the message forwards the message by direct delivery. Although the algorithm limits the number of copies of the message to a certain extent, the number of copies of the message is not set according to the properties of the network during the design of the routing algorithm. At the same time, factors such as node energy and node movement speed are not considered during the node selection process, which makes the network unable to achieve good performance. Summary of the invention

[0006] The purpose of the present invention is to solve the problem that the traditional opportunistic network routing method cannot enable the network to obtain better performance. The present invention provides an opportunistic network routing method based on adaptive clustering.

[0007] An opportunistic network routing method based on adaptive cluster partitioning comprises the following steps:

[0008] Step 1: Set the update period T of the global active nodes;

[0009] Step 2: After determining the global active nodes of the network, cluster the network according to geographical regions;

[0010] Step 3: Determine whether the number of global active nodes n1 contained in each cluster is greater than or equal to 1. If yes, execute step 4; otherwise, execute step 5;

[0011] Step 4: Determine the cluster head node of the cluster according to the cluster head determination method 1, and execute step 6;

[0012] Step 5: Determine the cluster head node of the cluster according to cluster head determination method 2, and execute step 6;

[0013] Step 6: Determine whether each node in the network generates a new message m. If so, the node is used as the source node and executes step 7; otherwise, execute step 8;

[0014] Step 7, after setting the number of copies of the generated new message m according to the message copy number setting method, execute step 8;

[0015] The method for setting the number of message copies is implemented as follows:

[0016] When the source node node(i′) and the destination node node(j) of the new message m are in the same cluster, set the number of copies of the new message m carried by the source node node(i′)

[0017] When the source node node(i′) and the destination node node(j) are not in the same cluster, set the number of copies of the new message m carried by the source node node(i′)

[0018] Among them, σ1 and σ2 are the first and second adjustment coefficients, which are positive real numbers, and σ1 is less than σ2. The intermediate variable Me(i′,j) is the number of historical encounters between the source node node(i′) and the destination node node(j), k is the feedback coefficient, and the initial value of k is 1;

[0019] Step 8: Determine whether each node in the network has a message to be forwarded. If yes, execute step 9; otherwise, execute step 6.

[0020] Step 9: Determine whether there is a destination node among the optional nodes within the communication range. If yes, directly forward the message to the destination node and execute step 14; otherwise, execute step 10;

[0021] Step 10: Determine whether there is a cluster head node among the optional nodes within the communication range. If yes, select the cluster head node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Execute step 14; otherwise, execute step 11;

[0022] Step 11: If there is no cluster head node among the optional nodes, determine whether there is a node in the same cluster as the destination node or a globally active node among the optional nodes within the communication range. If yes, execute step 12; otherwise, execute step 13.

[0023] Step 12: Among all the optional nodes, select the node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Go to step 14.

[0024] Step 13: Among all the optional nodes, select the node with the largest forwarding weight as the relay node. The number of message copies obtained by the relay node is Go to step 14.

[0025] Step 14: Determine whether the duration of the global active node reaches the update period T. If yes, execute step 15; otherwise, execute step 6;

[0026] Step 15: determine whether the network delivery rate is greater than the delivery rate threshold ψ, where delivery rate = number of messages delivered to the destination node by the entire network in the current cycle / total number of new messages generated by the entire network; if yes, return to step 1; otherwise, execute step 16;

[0027] Step 16: Determine whether the message discard rate in the network is greater than the discard rate threshold τ, where discard rate = number of messages discarded by all nodes in the entire network in the current cycle / total number of new messages and duplicate messages generated by the entire network; if yes, execute step 17; otherwise, execute step 18;

[0028] Step 17, reduce the k value and update k, the update method is k=max{k-θ,0.5}, 0<θ<1, execute step 1; θ is the third adjustment coefficient;

[0029] Step 18: Increase the k value and update k, k=min{k+θ,2}, 0<θ<1, execute step 1, θ is the third adjustment coefficient.

[0030] Preferably, the global active nodes of the opportunistic network are determined by:

[0031] For any node node(i) in the network, calculate the global activity value Wnode(i) of node node(i). If Wnode(i) is greater than the threshold η, define node node(i) as a globally active node. Otherwise, do not define node node(i) as a globally active node. The value of η is a positive real number.

[0032] Preferably, Wnode(i)=α1×SP(i)+α2×BU(i)+α3×EN(i)+α4×MS(i)+α5×RE(i);

[0033] Among them, SP(i) is the moving speed of node node(i), BU(i) is the remaining cache of node node(i), EN(i) is the remaining energy of node node(i), MS(i) is the moving distance of node node(i), RE(i) is the number of times node node(i) receives messages, α1+α2+α3+α4+α5=1, α1 is the moving speed coefficient, α2 is the remaining cache coefficient, α3 is the remaining energy coefficient, α4 is the moving distance coefficient, and α5 is the number of times message reception is coefficient.

[0034] Preferably, the cluster head determination method 1 is implemented as follows:

[0035] If the cluster contains only one globally active node, the globally active node is used as the cluster head node of the cluster. Otherwise, the largest front node in the remaining cache in the cluster is used as the cluster head node. The globally active nodes are used as the cluster head nodes of the cluster, N1 is the total number of nodes in the cluster, N is the total number of nodes in the network, δ is the fourth adjustment coefficient, and its value is a positive real number.

[0036] Preferably, the cluster head determination method 2 is implemented as follows:

[0037] Select a node with the largest local activity value in the cluster as the cluster head node of the cluster, where the local activity value of the node node(p) in the cluster is The expression is:

[0038]

[0039] Among them, β1+β2=1, BU(p) is the remaining buffer of node node(p), MS(p) is the moving distance of node node(p), and β1 and β2 are both intra-cluster proportional adjustment coefficients.

[0040] Preferably, the expression of the forwarding weight value WT(q) of the optional node node(q) is:

[0041] WT(q)=λ1×SP(q)+λ2×BU(q)+λ3×EN(q)+λ4×Me(q,j)+λ5×MS(q);

[0042] Among them, SP(q) is the moving speed of the optional node node(q) within the communication range, BU(q) is the remaining cache of the optional node node(q) within the communication range, EN(q) is the remaining energy of the optional node node(q) within the communication range, Me(q,j) is the number of historical encounters between the optional node node(q) within the communication range and the destination node node(j), MS(q) is the moving distance of the optional node node(q) within the communication range, λ1+λ2+λ3+λ4+λ5=1, λ1 to λ5 are all proportional adjustment coefficients of the optional nodes within the communication range.

[0043] Preferably, ψ is a real number greater than 0.5 and less than 1.

[0044] Preferably, τ is a real number greater than 0.5 and less than 1.

[0045] Preferably, 0.5≤k≤2.

[0046] Advantages of the present invention:

[0047] (1) The present invention sets the update period T of the global active node, so that in each period T, the network can select nodes that are more conducive to enhancing network performance as global active nodes, and further in the message forwarding process, the message forwarding can be completed with a higher delivery rate. In addition, the method also adjusts the number of copies of the newly generated message in the next period according to the delivery rate and discard rate of the network in the previous period, so that the network resources can be effectively utilized without affecting the network message delivery rate.

[0048] (2) When a node generates a message, the number of copies of the message is initially set based on factors such as whether the source node and the destination node are in the same cluster and the number of encounters between the nodes. By limiting the number of copies of the message, network resources can be effectively utilized.

[0049] (3) In the relay node selection process, globally active nodes or cluster head nodes are given priority as relay nodes, which can enable messages to be forwarded by relay nodes that are more likely to be delivered to the destination node. In addition, when the selected relay node is a globally active node or a cluster head node, more message copies are allocated to the relay node, so that the network delivery rate is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 is a flow chart of the opportunistic network routing method based on adaptive cluster partitioning according to the present invention;

[0051] Figure 2 It is the distribution relationship diagram of the global active nodes and cluster head nodes in each cluster after the network is clustered. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0054] See also Figure 1 and Figure 2 The present embodiment describes an opportunistic network routing method based on adaptive clustering, which comprises the following steps:

[0055] Step 1: Set the update period T of the global active nodes;

[0056] Step 2: After determining the global active nodes of the network, cluster the network according to geographical regions;

[0057] Step 3: Determine whether the number of global active nodes n1 contained in each cluster is greater than or equal to 1. If yes, execute step 4; otherwise, execute step 5;

[0058] Step 4: Determine the cluster head node of the cluster according to the cluster head determination method 1, and execute step 6;

[0059] Step 5: Determine the cluster head node of the cluster according to cluster head determination method 2, and execute step 6;

[0060] Step 6: Determine whether each node in the network generates a new message m. If so, the node is used as the source node and executes step 7; otherwise, execute step 8;

[0061] Step 7, after setting the number of copies of the generated new message m according to the message copy number setting method, execute step 8;

[0062] The method for setting the number of message copies is implemented as follows:

[0063] When the source node node(i′) and the destination node node(j) of the new message m are in the same cluster, set the number of copies of the new message m carried by the source node node(i′)

[0064] When the source node node(i′) and the destination node node(j) are not in the same cluster, set the number of copies of the new message m carried by the source node node(i′)

[0065] Among them, σ1 and σ2 are the first and second adjustment coefficients, which are positive real numbers, and σ1 is less than σ2. The intermediate variable Me(i′,j) is the number of historical encounters between the source node node(i′) and the destination node node(j), k is the feedback coefficient, and the initial value of k is 1;

[0066] Step 8: Determine whether each node in the network has a message to be forwarded. If yes, execute step 9; otherwise, execute step 6.

[0067] Step 9: Determine whether there is a destination node among the optional nodes within the communication range. If yes, directly forward the message to the destination node and execute step 14; otherwise, execute step 10;

[0068] Step 10: Determine whether there is a cluster head node among the optional nodes within the communication range. If yes, select the cluster head node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Execute step 14; otherwise, execute step 11;

[0069] Step 11: If there is no cluster head node among the optional nodes, determine whether there is a node in the same cluster as the destination node or a globally active node among the optional nodes within the communication range. If yes, execute step 12; otherwise, execute step 13.

[0070] Step 12: Among all the optional nodes, select the node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Go to step 14.

[0071] Step 13: Among all the optional nodes, select the node with the largest forwarding weight as the relay node. The number of message copies obtained by the relay node is Go to step 14.

[0072] Step 14: Determine whether the duration of the global active node reaches the update period T. If yes, execute step 15; otherwise, execute step 6;

[0073] Step 15: determine whether the network delivery rate is greater than the delivery rate threshold ψ, where delivery rate = number of messages delivered to the destination node by the entire network in the current cycle / total number of new messages generated by the entire network; if yes, return to step 1; otherwise, execute step 16;

[0074] Step 16: Determine whether the message discard rate in the network is greater than the discard rate threshold τ, where discard rate = number of messages discarded by all nodes in the entire network in the current cycle / total number of new messages and duplicate messages generated by the entire network; if yes, execute step 17; otherwise, execute step 18;

[0075] Step 17, reduce the k value and update k, the update method is k=max{k-θ,0.5}, 0<θ<1, execute step 1; θ is the third adjustment coefficient;

[0076] Step 18: Increase the k value and update k, k=min{k+θ,2}, 0<θ<1, execute step 1, θ is the third adjustment coefficient.

[0077] In specific applications, ψ is a real number greater than 0.5 and less than 1, τ is a real number greater than 0.5 and less than 1, and 0.5≤k≤2. In this preferred embodiment, by setting the update period T of the global active node, the network can select nodes that are more conducive to enhancing network performance as global active nodes in each period T, and further in the message forwarding process, the message forwarding can be completed with a higher delivery rate. In addition, the method also adjusts the number of copies of the newly generated message in the next period according to the delivery rate and discard rate of the network in the previous period, so that the network resources can be effectively utilized without affecting the network message delivery rate.

[0078] When a node generates a message, the number of copies of the message is initially set based on factors such as whether the source node and the destination node are in the same cluster and the number of encounters between the nodes. By limiting the number of copies of the message, network resources can be effectively utilized.

[0079] In the relay node selection process, the globally active node or cluster head node is preferentially selected as the relay node, so that the message can be forwarded by the relay node that is more likely to be delivered to the destination node. In addition, when the selected relay node is a globally active node or cluster head node, more message copies are allocated to the relay node, so that the network delivery rate is further improved.

[0080] The messages in the present invention include new messages and copy messages generated by nodes.

[0081] In specific applications, the network is clustered according to geographical areas. Specifically, the geographical areas where all nodes in the network are located are divided, and each area is regarded as a cluster.

[0082] Specifically, the implementation method of determining the global active nodes of the opportunistic network is as follows:

[0083] For any node node(i) in the network, calculate the global activity value Wnode(i) of node node(i). If Wnode(i) is greater than the threshold η, define node node(i) as a globally active node. Otherwise, do not define node node(i) as a globally active node. The value of η is a positive real number.

[0084] In this preferred embodiment, the global activity value of each node is calculated to define whether it is a globally active node, and globally active nodes are preferentially selected as relay nodes, so that messages can be forwarded by relay nodes that are more likely to be delivered to the destination node, thereby enhancing network performance.

[0085] In specific applications, the expression of the global active value Wnode(i) of node node(i) is:

[0086] Wnode(i)=α1×SP(i)+α2×BU(i)+α3×EN(i)+α4×MS(i)+α5×RE(i);

[0087] Among them, SP(i) is the moving speed of node node(i), BU(i) is the remaining cache of node node(i), EN(i) is the remaining energy of node node(i), MS(i) is the moving distance of node node(i), RE(i) is the number of times node node(i) receives messages, α1+α2+α3+α4+α5=1, α1 is the moving speed coefficient, α2 is the remaining cache coefficient, α3 is the remaining energy coefficient, α4 is the moving distance coefficient, and α5 is the number of times message reception is coefficient.

[0088] In this preferred embodiment, the global activity value Wnode(i) comprehensively considers the moving speed of node node(i), the remaining cache of node node(i), the remaining energy of node node(i), the moving distance of node node(i) and the number of times node node(i) receives messages, so that the resources of the network are effectively utilized and comprehensive considerations are taken into account.

[0089] It is further given that the implementation method of cluster head determination method 1 is:

[0090] If the cluster contains only one globally active node, the globally active node is used as the cluster head node of the cluster. Otherwise, the largest front node in the remaining cache in the cluster is used as the cluster head node. The globally active nodes are used as the cluster head nodes of the cluster, N1 is the total number of nodes in the cluster, N is the total number of nodes in the network, δ is the fourth adjustment coefficient, and its value is a positive real number.

[0091] The preferred implementation scheme defines the principle of selecting a cluster head node when a cluster contains multiple globally active nodes. The advantage of this selection method is that the number of cluster head nodes is determined based on the ratio of the total number of nodes in the cluster to the total number of nodes in the network, so that the determined number of cluster head nodes is not too many or too few. Secondly, nodes with large remaining cache are selected as cluster head nodes, which helps to effectively utilize resources during message transmission.

[0092] It is further given that the implementation method of cluster head determination method 2 is:

[0093] Select a node with the largest local activity value in the cluster as the cluster head node of the cluster, where the local activity value of the node node(p) in the cluster is The expression is:

[0094]

[0095] Among them, β1+β2=1, BU(p) is the remaining buffer of node node(p), MS(p) is the moving distance of node node(p), and β1 and β2 are both intra-cluster proportional adjustment coefficients.

[0096] In this preferred implementation, a principle for selecting a cluster head node when there is no globally active node in the cluster is given. The advantage of this selection method is that the cluster head is selected by the node's cache and the node's moving distance, so that nodes with larger cache space and longer moving distance will be selected as cluster head nodes, which helps to improve the message delivery rate during message forwarding.

[0097] Specifically, the expression of the forwarding weight value WT(q) of the optional node node(q) is:

[0098] WT(q)=λ1×SP(q)+λ2×BU(q)+λ3×EN(q)+λ4×Me(q,j)+λ5×MS(q);

[0099] Among them, SP(q) is the moving speed of the optional node node(q) within the communication range, BU(q) is the remaining cache of the optional node node(q) within the communication range, EN(q) is the remaining energy of the optional node node(q) within the communication range, Me(q,j) is the number of historical encounters between the optional node node(q) within the communication range and the destination node node(j), MS(q) is the moving distance of the optional node node(q) within the communication range, λ1+λ2+λ3+λ4+λ5=1, λ1 to λ5 are all proportional adjustment coefficients of the optional nodes within the communication range.

[0100] In this preferred embodiment, an expression for the forwarding weight value WT(q) of the optional node node(q) is given, which comprehensively considers the moving speed of the optional node node(q), the remaining cache of the optional node node(q), the remaining energy of the optional node node(q), the historical number of encounters between the optional node node(q) and the destination node node(j), and the moving distance of the optional node node(q). The resources of the network are effectively utilized and comprehensive considerations are taken into account, providing a more comprehensive data basis for the selection of relay nodes.

[0101] Principle analysis: The present invention proposes an opportunistic network routing method based on adaptive clustering. The method first sets the initial value of the update period T of the global active node, and determines the global active node according to the global active node determination method. Secondly, the method clusters the network according to geographical areas, and selects cluster head nodes for each cluster. When the node generates a message, the number of copies of the message is initially set to limit the total number of copies of the message in the network. When a node has a message to be forwarded, it selects an appropriate node as a relay node based on whether there is a cluster head node, a global active node, etc. among the optional nodes, and completes the message forwarding. Finally, when the update period T of the global active node is reached, the initial number of copies of the message in the next update period of the global active node is adjusted based on the network's delivery rate, discard rate and other performance.

[0102] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. An opportunistic network routing method based on adaptive clustering, characterized in that: The method comprises the following steps: Step 1: Set the update period T of the global active nodes; Step 2: After determining the global active nodes of the network, cluster the network according to geographical regions; Step 3: Determine whether the number of global active nodes n1 contained in each cluster is greater than or equal to 1. If so, execute step 4. Otherwise, go to step 5; Step 4: Determine the cluster head node of the cluster according to the cluster head determination method 1, and execute step 6; Step 5: Determine the cluster head node of the cluster according to cluster head determination method 2, and execute step 6; Step 6: Determine whether each node in the network generates a new message m. If so, the node is used as the source node and executes step 7; Otherwise, go to step 8; Step 7, after setting the number of copies of the generated new message m according to the message copy number setting method, execute step 8; The method for setting the number of message copies is implemented as follows: When the source node node(i′) and the destination node node(j) of the new message m are in the same cluster, set the number of copies of the new message m carried by the source node node(i′) When the source node node(i′) and the destination node node(j) are not in the same cluster, set the number of copies of the new message m carried by the source node node(i′) Among them, σ1 and σ2 are the first and second adjustment coefficients, which are positive real numbers, and σ1 is less than σ2. The intermediate variable Me(i′,j) is the number of historical encounters between the source node node(i′) and the destination node node(j), k is the feedback coefficient, and the initial value of k is 1; Step 8: Determine whether each node in the network has a message to be forwarded. If yes, execute step 9; otherwise, execute step 6. Step 9: Determine whether there is a destination node among the optional nodes within the communication range. If yes, directly forward the message to the destination node and execute step 14; otherwise, execute step 10; Step 10: Determine whether there is a cluster head node among the optional nodes within the communication range. If yes, select the cluster head node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Execute step 14; otherwise, execute step 11; Step 11: If there is no cluster head node among the optional nodes, determine whether there is a node in the same cluster as the destination node or a globally active node among the optional nodes within the communication range. If yes, execute step 12; otherwise, execute step 13. Step 12: Among all the optional nodes, select the node with the largest remaining cache as the relay node. The number of message copies obtained by the relay node is Go to step 14. Step 13: Among all the optional nodes, select the node with the largest forwarding weight as the relay node. The number of message copies obtained by the relay node is Go to step 14. Step 14: Determine whether the duration of the global active node reaches the update period T. If yes, execute step 15; otherwise, execute step 6; Step 15: determine whether the network delivery rate is greater than the delivery rate threshold ψ, where delivery rate = number of messages delivered to the destination node by the entire network in the current cycle / total number of new messages generated by the entire network; if yes, return to step 1; otherwise, execute step 16; Step 16: Determine whether the message discard rate in the network is greater than the discard rate threshold τ, where discard rate = number of messages discarded by all nodes in the entire network in the current cycle / total number of new messages and duplicate messages generated by the entire network; if yes, execute step 17; otherwise, execute step 18; Step 17, reduce the k value and update k, the update method is k=max{k-θ,0.5}, 0<θ<1, execute step 1; θ is the third adjustment coefficient; Step 18: Increase the k value and update k, k=min{k+θ,2}, 0<θ<1, execute step 1, θ is the third adjustment coefficient.

2. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: The implementation method of determining the global active nodes of the opportunistic network is: For any node node(i) in the network, calculate the global activity value Wnode(i) of node node(i). If Wnode(i) is greater than the threshold η, define node node(i) as a globally active node. Otherwise, do not define node node(i) as a globally active node. The value of η is a positive real number.

3. The opportunistic network routing method based on adaptive clustering according to claim 2, characterized in that: Wnode(i)=α1×SP(i)+α2×BU(i)+α3×EN(i)+α4×MS(i)+α5×RE(i); Among them, SP(i) is the moving speed of node node(i), BU(i) is the remaining cache of node node(i), EN(i) is the remaining energy of node node(i), MS(i) is the moving distance of node node(i), RE(i) is the number of times node node(i) receives messages, α1+α2+α3+α4+α5=1, α1 is the moving speed coefficient, α2 is the remaining cache coefficient, α3 is the remaining energy coefficient, α4 is the moving distance coefficient, and α5 is the number of times message reception is coefficient.

4. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: The implementation of cluster head determination method 1 is as follows: If the cluster contains only one globally active node, the globally active node is used as the cluster head node of the cluster. Otherwise, the largest front node in the remaining cache in the cluster is used as the cluster head node. The globally active nodes are used as the cluster head nodes of the cluster, N1 is the total number of nodes in the cluster, N is the total number of nodes in the network, δ is the fourth adjustment coefficient, and its value is a positive real number.

5. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: The implementation of cluster head determination method 2 is as follows: Select a node with the largest local activity value in the cluster as the cluster head node of the cluster, where the local activity value of the node node(p) in the cluster is The expression is: Among them, β1+β2=1, BU(p) is the remaining buffer of node node(p), MS(p) is the moving distance of node node(p), and β1 and β2 are both intra-cluster proportional adjustment coefficients.

6. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: The expression of the forwarding weight value WT(q) of the optional node node(q) is: WT(q)=λ1×SP(q)+λ2×BU(q)+λ3×EN(q)+λ4×Me(q,j)+λ5×MS(q); Among them, SP(q) is the moving speed of the optional node node(q) within the communication range, BU(q) is the remaining cache of the optional node node(q) within the communication range, EN(q) is the remaining energy of the optional node node(q) within the communication range, Me(q,j) is the number of historical encounters between the optional node node(q) within the communication range and the destination node node(j), MS(q) is the moving distance of the optional node node(q) within the communication range, λ1+λ2+λ3+λ4+λ5=1, λ1 to λ5 are all proportional adjustment coefficients of the optional nodes within the communication range.

7. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: ψ is a real number greater than 0.5 and less than 1.

8. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: τ is a real number greater than 0.5 and less than 1.

9. The opportunistic network routing method based on adaptive clustering according to claim 1, characterized in that: 0.5≤k≤2。

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