Routing Method for Achieving High-Reliability and Low-Overhead Transmission in Large-Scale Sensor Networks

Abstract

The present invention discloses a routing method for achieving highly reliable and low-overhead transmission in a large-scale sensor network. It mainly solves the problems of uneven network energy consumption, inapplicability to highly reliable services, and large routing maintenance overhead in the prior art. The implementation solution is as follows: The root node broadcasts DIO messages; network nodes receive DIO messages, use triangular fuzzy functions to construct objective functions, and calculate routing metrics for low power consumption and high reliability respectively according to the node information in the messages using the objective functions; select the optimal parent node for access according to the routing metrics, and establish low-power routing and high-reliability routing respectively; use Bloom filters to compress routing maintenance information; for the routes that hit the Bloom filter, reply to the routing state through a dual-state interval mechanism to avoid the loss of routing maintenance information. The present invention can effectively balance the network load, extend the network lifespan, achieve an efficient balance between energy consumption and reliability, and can be used in large-scale sensor networks.

Description

Technical Field

[0001] The present invention belongs to the field of communication technologies, and further relates to a routing method for high-reliability and low-overhead transmission, which can be used in large-scale sensor networks. Background Art

[0002] A wireless sensor network is a distributed sensing network. Due to its characteristics of low data rate, low energy consumption, and short-distance links, and its ability to monitor the physical world on an unprecedented scale, it is considered an effective solution for large-scale tracking and monitoring applications. In living and production environments such as homes and factories, by deploying a large number of small wireless sensors, and through sampling and processing, the data information collected by them can be transmitted to external systems such as base stations and the Internet, thus opening up many new application fields.

[0003] A low-power and lossy network is a special multi-hop, centerless, and self-organizing wireless sensor network with a wide range of applications. However, traditional routing protocols are not applicable to low-power and lossy networks. Therefore, the Internet Engineering Task Force has studied and developed the RPL routing protocol specifically for low-power and lossy networks. Starting from the goal of low power consumption, this protocol improves the lifespan of wireless sensor networks.

[0004] In traditional sensor networks, the design of routing protocols aims at low power consumption as the ultimate goal and supports periodic services. However, only focusing on low power consumption while ignoring the service quality requirements of services may lead to the loss of timeliness or even data loss when transmitting sensitive data, and the requirement to quickly and reliably send data to the processing center often means higher power consumption. Therefore, in the context of the increasingly widespread application of the Internet of Things, how to balance the high service quality requirements for the effectiveness and reliability of data while reducing network power consumption has become an urgent problem to be solved. At the same time, for storage-based routing protocols, each network node needs to maintain the routing to downstream nodes. When the network scale increases, the bandwidth occupation and power consumption in the routing maintenance process increase sharply, resulting in a serious shortening of the network lifespan. Therefore, it is necessary to design simple information compression for routing maintenance information to reduce the maintenance overhead.

[0005] A routing method for a lunar communication system based on the low-power lossy network routing protocol RPL is proposed in the patent document with the application number CN202011550976.8, which is used to solve the technical problems of high average energy consumption of nodes, uneven energy consumption of each node, and large forwarding overhead of routing table information in the prior art. The implementation steps are as follows: setting parameters; each communication node constructs its own information object message based on the RPL message format; each node selects its own parent node based on the characteristics of the lunar surface rotation period; constructing an RPL network topology in a non-storage mode. Although this method can reduce the node routing overhead to a certain extent and extend the network life, due to only considering the node power supply status and logical hop count during the routing establishment process, without considering other influencing factors such as the reliability of the link between nodes, the remaining energy of nodes, and the congestion of the cache queue, it is impossible to comprehensively improve the network life. In addition, due to not considering the reliability problem of data, it cannot be competent for services with high reliability requirements, which will lead to the loss of sensitive data collected by sensor nodes or the loss of timeliness due to delay. Summary of the Invention

[0006] The object of the present invention is to propose a routing method for realizing high-reliability and low-overhead transmission in a large-scale sensor network in view of the above-mentioned deficiencies of the prior art, so as to extend the network life and improve the reliability of sensitive data transmission.

[0007] The technical solution of the present invention respectively considers various factors affecting energy consumption and reliability, and applies the triangular fuzzy function to map multiple influencing factors into evaluation indicators of low power consumption and high reliability, so as to realize the establishment of a low-power and high-reliability dual-objective routing; using the Bloom filter to compress the routing information and constructing a query table and a reply table for the routes to be maintained for node-to-node interaction to reduce the routing maintenance overhead. The implementation steps include the following:

[0008] (1) The root node broadcasts the information object message DIO, and this DIO message includes basic information such as power supply status, logical hop count, remaining energy, expected retransmission times, expected node life, and congestion status that meet the requirements of the dual-objective function;

[0009] (2) The network node receives the DIO message and constructs a potential parent node table of the network node according to the received DIO message, and this table needs to contain at least one node information;

[0010] (3) The network node determines whether to construct a potential parent node table according to the service type of the personal area network identifier PAN ID in the DIO message;

[0011] If the service of this node belongs to the PAN ID category, construct a potential parent node table and execute step (4);

[0012] Otherwise, reject constructing the potential parent node table and return to step (2);

[0013] (4) Select the optimal parent node:

[0014] (4a) Take the power supply status, logical hop count, remaining energy, expected retransmission times, and node expected lifetime of each potential parent node in the potential parent node table as parameters and input them into a fifth-order triangular fuzzy function to calculate the Rank value of the low-power consumption target. Take the logical hop count, expected retransmission times, and congestion status as parameters and input them into a third-order triangular fuzzy function to calculate the Rank value of the high-reliability target;

[0015] (4b) Select the maximum values of the Rank values of the low-power consumption target and the high-reliability target respectively from the calculation results in (4a), and elect the nodes corresponding to the maximum values as the low-power consumption optimal parent node and the high-reliability optimal parent node respectively;

[0016] (5) Send node information to the root node through the optimal parent node and establish a route:

[0017] (5a) The network node sends a DIS message according to whether the two parent nodes are the same node:

[0018] If the low-energy consumption optimal parent node and the high-reliability optimal parent node are the same node, unicast an information request packet DIS with low-power consumption and high-reliability identifiers to the root node through this node;

[0019] If the low-power consumption optimal parent node and the high-reliability optimal parent node are not the same node, unicast a DIS message with a low-energy consumption identifier and a DIS message with a high-reliability identifier to the root node through the two optimal parent nodes respectively;

[0020] (5b) The nodes on the path during the unicast process receive and forward the DIS message, and establish a low-power consumption route or a high-reliability route to the DIS message source node according to the DIS identifier, and at the same time start a route maintenance timer;

[0021] (6) The network node updates the local node information according to the latest network status and periodically broadcasts a DIO message carrying the local node information to the channel;

[0022] (7) The network node judges whether route maintenance is required according to the status of the route maintenance timer:

[0023] If the route maintenance timer expires, route maintenance needs to be performed. The requesting node adds the route information to be maintained with the same next hop to the set to be maintained and executes step (8);

[0024] Otherwise, route maintenance is not required, and wait for the timer to expire;

[0025] (8) The requesting node compresses the routes in the set to be maintained through a Bloom filter, and sends the compressed route information as the payload of the route maintenance request message to the next-hop node;

[0026] (9) After receiving the request, the receiving node attempts to match the route information in its local routing table with the compressed information carried in the request one by one using the same Bloom filter, and determines whether it is a route to be maintained based on the attempt results:

[0027] If a route matches the compressed information, then this route is a route to be maintained, and step (10) is executed.

[0028] Otherwise, it is not a route to be maintained and no operation is required;

[0029] (10) The receiving node, according to the status of the route to be maintained, puts the active routes compressed through the Bloom filter into the active interval, puts the inactivated routes after compression into the inactivated interval, and sends the information of the two intervals as the payload of the route maintenance reply message to the requesting node;

[0030] (11) After receiving the route maintenance reply message, the requesting node attempts to match the routes to be maintained with the two intervals respectively, and updates the route status according to the attempt results:

[0031] If it matches the active interval and does not match the inactivated interval, then update this route to the active state;

[0032] If it does not match the active interval and matches the inactivated interval, then update this route to the inactivated state;

[0033] If it matches both intervals, it means that this route has lost information due to a conflict with other routes with different states during the compression process and the route status cannot be determined, and step (12) is executed;

[0034] (12) The requesting node directly sends the route whose status cannot be determined as the payload of the route maintenance request message to the next-hop node;

[0035] (13) The receiving node queries the status of the route to be queried in the route maintenance request message in its local routing table, and sends the status directly as the payload of the route maintenance reply message to the requesting node;

[0036] (14) The requesting node receives the route maintenance message and updates its local route according to the route status information in the payload.

[0037] The present invention has the following advantages compared with the prior art:

[0038] First, compared with the existing routing protocols that only consider the node power supply status and logical hop count as the objective function, the present invention comprehensively considers multiple influencing factors, including the power supply status, logical hop count, remaining energy, expected transmission times, expected node lifetime, and congestion status, and can effectively balance the network load and extend the network lifetime.

[0039] Second, the present invention constructs a dual-objective function for low power consumption and high reliability. Compared with the existing technologies that use a single-objective function, by analyzing the influencing factors and network service requirements, the routing selection strategy is dynamically adjusted, and while meeting the service requirements, an efficient balance between energy consumption and reliability can be achieved.

[0040] Third, compared with the method in the existing routing maintenance algorithms that need to add complete address information to the routing maintenance message, the present invention uses a Bloom filter during the maintenance process, which can compress the byte-level routing information in the routing maintenance message to the bit level, effectively compressing the length of the message. At the same time, two mapping tables are used to reply to the routing maintenance result, which can avoid the routing maintenance failure problem caused by the loss of routing information due to hash conflicts, and further extend the network lifetime. Description of the Drawings

[0041] Figure 1 is the overall flowchart of the implementation of the present invention;

[0042] Figure 2 is the sub-flowchart of establishing a route in the present invention;

[0043] Figure 3 is the sub-flowchart of route maintenance in the present invention;

[0044] Figure 4 is the double-interval schematic diagram of the route maintenance reply message in the present invention. Detailed Embodiment

[0045] The following further describes the embodiments of the present invention in detail with reference to the drawings.

[0046] This embodiment comprehensively considers various factors affecting energy consumption and reliability, maps multiple influencing factors to the evaluation indexes for establishing low-energy-consumption and high-reliability routes respectively, so as to realize the establishment of a dual-objective route for low power consumption and high reliability. And a route maintenance scheme with dual-state auxiliary information calibration for routing information compression is adopted to further reduce the routing maintenance overhead.

[0047] The implementation steps of this embodiment are as follows:

[0048] Step 1, the root node completes initialization and initiates network formation.

[0049] Take the central node of the sensor network as the root node. The root node selects a Personal Area Network Identifier (PAN ID) according to the service type of the network, initializes the logical hop count to 0, initializes the expected transmission count to 1, sets the remaining energy as the initialized energy, initializes the expected node lifetime to the maximum value, and sets the congestion status to 0;

[0050] The root node initiates network formation and broadcasts its Information Object message DIO. This DIO message includes basic information such as PAN ID, power supply status, logical hop count, remaining energy, expected retransmission count, expected node lifetime, and congestion status that meet the requirements of the dual-objective function.

[0051] Step 2, the network node listens to the channel and waits to receive the DIO message.

[0052] 2.1) The network node listens to the channel and receives the channel message;

[0053] 2.2) Judge the received message:

[0054] If the received message is a DIO message, receive and parse the message, and execute step 3);

[0055] Otherwise, directly discard the DIO message and continue to listen to the channel.

[0056] Step 3, the network node determines whether the DIO message meets the access standard.

[0057] The access standard is that the service of the network node belongs to the service category of the PAN ID in the DIO message. Only the network accessed through the DIO that meets the standard can transmit the node service to the correct network center. Therefore, it is necessary to first determine whether the DIO message meets the access standard:

[0058] If the DIO message meets the standard, execute step 4);

[0059] Otherwise, discard the DIO message and return to step 2);

[0060] Step 4, the network node creates a potential parent node table according to the DIO message and elects the optimal parent node.

[0061] The potential parent node refers to the node through which the network node can connect to the root node, and the potential parent node table refers to the information table composed of these potential parent nodes. The optimal parent node refers to the node with the lowest impact on network power consumption or the best reliability after access in the potential parent node table.

[0062] Refer to Figure 2 For the specific implementation of this step, it is as follows:

[0063] 4.1) Use two objective functions as the election metrics for the low-power optimal parent node and the high-reliability optimal parent node respectively:

[0064] 4.1.1) The low-power objective function uses a fifth-order triangular fuzzy function, which is expressed as follows:

[0065]

[0066] Where, are five input parameters, represents the j-th input parameter, the value range of j is [1, 5], the value range of the input parameter is [0, 1], and Π· represents the product operation;

[0067] 4.1.2) The high-reliability objective function uses a third-order triangular fuzzy function, which is expressed as follows:

[0068]

[0069] Where, x, y, w are three input parameters, and the value range of each input parameter is [0, 1];

[0070] 4.2) Normalize the information in the potential parent node table:

[0071] 4.2.1) Take the ratio of the current power supply capacity to the initial energy as the normalization result of the power supply state;

[0072] 4.2.2) Normalize the node logical hop count using a Gaussian function, and the normalized node logical hop count is as follows:

[0073]

[0074] Where, h is the node logical hop count, and e is a constant;

[0075] 4.2.3) Normalize the remaining energy using the arctangent function to obtain the normalized remaining energy E norm :

[0076]

[0077] Where, π is a constant, E res is the remaining energy, and arctan(·) is the standard arctangent function;

[0078] 4.2.4) Take the ratio of the expected retransmission times to the maximum retransmission times as the normalization result of the expected retransmission times;

[0079] 4.2.5) Calculate and normalize the expected node lifetime:

[0080] 4.2.5.1) According to the remaining energy Eres Obtain the expected node lifetime EL based on the node's unit energy consumption P:

[0081]

[0082] 4.2.5.2) Normalize the expected node lifetime using the arctangent function to obtain the normalized expected node lifetime as follows:

[0083]

[0084] where π is a constant, EL is the expected node lifetime, and arctan(·) is the standard arctangent function;

[0085] 4.2.6) Use the ratio of the current queue length to the maximum length of the sending queue as the result of normalizing the congestion state;

[0086] 4.3) Calculate the routing metrics using the normalized information:

[0087] 4.3.1) Input the normalized power supply state, normalized logical hop count, normalized remaining energy, normalized expected retransmission times, and normalized expected node lifetime of each potential parent node in the potential parent node table into a fifth-order triangular fuzzy function to calculate the Rank value of the low-power consumption target;

[0088] 4.3.2) Input the normalized logical hop count, normalized expected retransmission times, and normalized congestion state of each potential parent node in the potential parent node table into a third-order triangular fuzzy function to calculate the Rank value of the high-reliability target;

[0089] 4.4) Select the maximum values of the Rank values of the low-power consumption target and the high-reliability target respectively from the calculation results in 4.3), and elect the nodes corresponding to the maximum values as the low-power consumption optimal parent node and the high-reliability optimal parent node respectively.

[0090] Step 5, Send node information to the root node through the optimal parent node and establish a route.

[0091] 5.1) The network node sends DIS messages according to whether the two parent nodes are the same node:

[0092] If the low-energy consumption optimal parent node and the high-reliability optimal parent node are the same node, unicast an information request message DIS with low-power consumption and high-reliability identifiers to the root node through this node;

[0093] If the low-power consumption optimal parent node and the high-reliability optimal parent node are not the same node, unicast a DIS message with a low-energy consumption identifier and a DIS message with a high-reliability identifier to the root node through the two optimal parent nodes respectively;

[0094] 5.2) During the unicast process, the nodes on the path receive and forward DIS messages, and establish routes according to the two flag bits of low power consumption and high reliability in the DIS message:

[0095] If the low power consumption flag bit is true and the high reliability flag bit is false, the DIS source node is used as the destination node, and the sending node is used as the next hop node and saved in the low power consumption routing table;

[0096] If the high reliability flag bit is true and the low power consumption flag bit is false, the DIS source node is used as the destination node, and the sending node is used as the next hop node and saved in the high reliability routing table.

[0097] If both the low power consumption and high reliability flag bits are true, the DIS source node is used as the destination node, and the sending node is used as the next hop node and saved in the low power consumption routing table and the high reliability routing table respectively.

[0098] 5.3) After the node establishes the route, start the route maintenance timer.

[0099] Step 6, the network node broadcasts DIO messages and determines the maintenance of the route.

[0100] 6.1) The network node updates the local node information according to the latest network status, and periodically broadcasts the information object packet DIO carrying the local node information to the channel;

[0101] 6.2) The network node determines whether to maintain the route according to the status of the route maintenance timer:

[0102] If the route maintenance timer has not expired, there is no need to perform route maintenance, and wait for the timer to expire;

[0103] If the route maintenance timer has expired, route maintenance needs to be performed. The requesting node adds the route information to be maintained with the same next hop to the set to be maintained, and executes step 7). This requesting node represents the node that needs to actively initiate a route maintenance request when the route timer expires.

[0104] Step 7, the requesting node sends a route maintenance request message.

[0105] Refer to Figure 3 , the specific implementation of this step is as follows:

[0106] 7.1) The requesting node uses a hash function set composed of k mutually independent hash functions:

[0107] Hash[i] = h1 + i * h2

[0108] Among them, Hash[i] represents the i-th function in the function set, the value range of i is [1, k], h1 is the shift exclusive-or hash function SAX, and h2 is the value of h1 logically right-shifted by 32 bits;

[0109] 7.2) Use the set of hash functions established in 7.1) to calculate k index values for the maintenance routing information, and set the bits corresponding to the k index values in the m-bit binary array to true;

[0110] 7.3) Use the binary array in 7.2) as the payload of the routing maintenance request message and send it to the next-hop node.

[0111] Step 8, the receiving node receives and processes the routing maintenance request.

[0112] 8.1) The receiving node receives and parses the routing maintenance request message;

[0113] 8.2) The receiving node maps the routes in the local routing table to the k bits in the routing request message using the same Bloom filter as the sending node, and then determines whether all the k bits are true:

[0114] If all the k bits are true, it means that the compressed information is hit, and this route is the route to be maintained, and step 9) is executed;

[0115] Otherwise, this route is not the route to be maintained and no operation is required.

[0116] Step 9, the receiving node replies with a routing maintenance reply message.

[0117] Refer to Figure 4 , the specific implementation of this step is as follows:

[0118] 9.1) The receiving node, according to the status of the route r i in the set of routes to be maintained R, puts the active routes into the active interval after compression by the Bloom filter, and puts the inactivated routes into the inactivated interval after compression;

[0119] 9.2) Use the information of the active interval and the inactivated interval as the payload of the routing maintenance reply message and send it to the requesting node.

[0120] Step 10, the requesting node receives and processes the routing maintenance reply message.

[0121] 10.1) After receiving the routing maintenance reply message, the requesting node attempts to hit the two intervals for the routes to be maintained respectively, and the implementation is as follows:

[0122] 10.1.1) The requesting node calculates k indexes for the routes in the set of routes to be maintained using the Bloom filter, and maps the k indexes to the active interval and the inactivated interval in the routing reply message respectively;

[0123] 10.1.2) Determine whether all the bits corresponding to the k indexes in the active interval are true:

[0124] If all k bits of the active interval are true, it indicates that the route hits the active interval;

[0125] Otherwise, it indicates that the route does not hit the active interval;

[0126] 10.1.3) Determine whether all the bit positions corresponding to the k indexes in the active interval are true:

[0127] If all k bits of the deactivated interval are true, it indicates that the route hits the deactivated interval;

[0128] Otherwise, it indicates that the route does not hit the deactivated interval;

[0129] 10.2) Update the route status according to the attempt result in 10.1):

[0130] If it hits the active interval but does not hit the deactivated interval, update the route to the active state;

[0131] If it does not hit the active interval but hits the deactivated interval, update the route to the deactivated state;

[0132] If it hits both intervals, it indicates that the route has lost information due to a conflict with a route in a different state during the compression process, and the route status cannot be determined. Execute step 11);

[0133] Step 11, maintain the route whose status cannot be determined.

[0134] 11.1) The requesting node directly sends the route with an undetermined status as the payload of the route maintenance request message to the next-hop node;

[0135] 11.2) The receiving node queries the status of the route to be queried in the route maintenance request message in the local routing table, and directly sends the status as the payload of the route maintenance reply message to the requesting node;

[0136] 11.3) The requesting node receives the route maintenance message and updates the local route according to the route status information in the payload.

[0137] The above description is only a specific example of the present invention and does not constitute any limitation to the present invention. Obviously, for professionals in the field, after understanding the content and principle of the present invention, various corrections and changes in form and details may be made without departing from the principle and structure of the present invention. However, these corrections and changes based on the idea of the present invention are still within the protection scope of the claims of the present invention.

Claims

1. A routing method for achieving highly reliable and low-overhead transmission in a large-scale sensor network, characterized in that, It includes the following implementation steps: (1) The root node broadcasts the information object message DIO, and this DIO message includes basic information such as power supply status, logical hop count, remaining energy, expected retransmission times, expected node lifetime, and congestion status that meet the requirements of the double objective function; (2) The network node receives the DIO message and constructs a potential parent node table of the network node according to the received DIO message, and this table needs to contain at least one node information; (3) The network node determines whether to construct a potential parent node table according to the service type of the personal area network identifier PAN ID in the DIO message: If the service of this node belongs to the PAN ID category, then construct a potential parent node table and execute step (4); Otherwise, reject constructing a potential parent node table and return to step (2); (4) Select the optimal parent node: (4a) Take the power supply status, logical hop count, remaining energy, expected retransmission times, and expected node lifetime of each potential parent node in the potential parent node table as parameters and input them into a fifth-order triangular fuzzy function to calculate the Rank value of the low-power consumption target. Take the logical hop count, expected retransmission times, and congestion status as parameters and input them into a third-order triangular fuzzy function to calculate the Rank value of the high-reliability target; (4b) Select the maximum values of the Rank values of the low-power consumption target and the high-reliability target respectively from the calculation results in (4a), and elect the nodes corresponding to the maximum values as the low-power consumption optimal parent node and the high-reliability optimal parent node respectively; (5) Send node information to the root node through the optimal parent node and establish a route: (5a) The network node sends a DIS message according to whether the two parent nodes are the same node: If the low-power consumption optimal parent node and the high-reliability optimal parent node are the same node, then unicast an information request message DIS with low-power consumption and high-reliability identifiers to the root node through this node; If the low-power consumption optimal parent node and the high-reliability optimal parent node are not the same node, then unicast a DIS message with a low-power consumption identifier and a DIS message with a high-reliability identifier to the root node through the two optimal parent nodes respectively; (5b) The nodes on the path during the unicast process receive and forward the DIS message, and establish a low-power consumption route or a high-reliability route to the DIS message source node according to the DIS identifier, and at the same time start a route maintenance timer; (6) The network node updates the local node information according to the latest network status and periodically broadcasts a DIO message carrying the local node information on the channel; (7) The network node determines whether to maintain the route according to the status of the route maintenance timer: If the route maintenance timer expires, then route maintenance needs to be performed. The requesting node adds the route information to be maintained with the same next hop to the set to be maintained and executes step (8); Otherwise, route maintenance does not need to be performed and waits for the timer to expire; (8) The requesting node compresses the routes in the set to be maintained through a Bloom filter and sends the compressed route information as the payload of the route maintenance request message to the next-hop node; (9) After receiving the request, the receiving node uses the same Bloom filter to attempt to match the routing information in the local routing table with the compressed information carried in the request one by one, and determines whether it is a route to be maintained based on the attempt results: If the route matches the compressed information, the route is a route to be maintained, and step (10) is executed. Otherwise, it is not a route to be maintained and no operation is required. (10) According to the status of the route to be maintained, the receiving node puts the active routes into the active interval after compression by the Bloom filter, puts the inactivated routes into the inactivated interval after compression, and sends the information of the two intervals as the payload of the routing maintenance reply message to the requesting node. (11) After receiving the routing maintenance reply message, the requesting node attempts to match the route to be maintained with the two intervals respectively, and updates the route status according to the attempt results: If it matches the active interval and does not match the inactivated interval, update the route to the active state. If it does not match the active interval and matches the inactivated interval, update the route to the inactivated state. If it matches both intervals, it means that the route has lost information due to a conflict with other routes with different statuses during the compression process, and the route status cannot be determined. Execute step (12). (12) The requesting node directly uses the route whose status cannot be determined as the payload of the routing maintenance request message and sends it to the next-hop node. (13) The receiving node queries the status of the route to be queried in the routing maintenance request message in the local routing table, and sends the status directly as the payload of the routing maintenance reply message to the requesting node. (14) After receiving the routing maintenance message, the requesting node updates the local route according to the route status information in the payload.

2. The method according to claim 1, wherein: In step (2), the potential parent node table of the network node is constructed according to the received DIO message. The power supply status, logical hop count, remaining energy, expected retransmission times, expected node lifetime, and congestion status information in the DIO message are bound to the DIO message source node and saved locally to form the potential parent node table.

3. The method according to claim 1, characterized in that: The 5th-order triangular fuzzy function in step (4a) is expressed as follows: Among them, are 5 input parameters, represents the j-th input parameter, where the value range of j is [1, 5], the value range of the input parameter is [0, 1], and Π· represents the cumulative multiplication operation.

4. The method according to claim 1, characterized in that: The 3rd-order triangular fuzzy function in step (4a) is expressed as follows: Among them, x, y, and w are three input parameters, and the value range of each input parameter is [0, 1].

5. The method according to claim 1, characterized in that: In step (5b), a low-power route or a high-reliability route to the DIS message source node is established according to the DIS identifier. After the node receives the DIS message, it is established according to the two flag bits of low power and high reliability in the DIS message: If the low-power flag bit is true and the high-reliability flag bit is false, the DIS source node is used as the destination node, and the sending node is used as the next-hop node and saved in the low-power routing table. If the high-reliability flag bit is true and the low-power flag bit is false, the DIS source node is used as the destination node, and the sending node is used as the next-hop node and saved in the high-reliability routing table. If both the low-power and high-reliability flag bits are true, the DIS source node is used as the destination node, and the sending node is used as the next-hop node and saved in the low-power routing table and the high-reliability routing table respectively.

6. The method according to claim 1, characterized in that: In step (8), the requesting node compresses the routes in the set to be maintained through the Bloom filter, and the implementation is as follows: (8a) The requesting node uses a set of hash functions consisting of k mutually independent hash functions: Hash[i] = h1 + i * h2 where Hash[i] represents the i-th function in the function set, the value range of i is [1, k], h1 is the shift exclusive-or hash function SAX, and h2 is the value obtained by logically right-shifting h1 by 32 bits; (8b) Use the set of hash functions established in (8a) as a Bloom filter, calculate k index values, and set the bit positions corresponding to the k index values in the m-bit binary array to true.

7. The method according to claim 1, characterized in that: In step (9), the receiving node uses the same Bloom filter to attempt to hit the compressed information carried in the request one by one. The receiving node first maps the routes in the local routing table to k bit positions in the route request message using the same Bloom filter, and then determines whether all k bit positions are true: If all k bit positions are true, it means that the compressed information is hit, and this route is a route to be maintained; Otherwise, this route is not a route to be maintained.

8. The method according to claim 1, wherein: In step (11), attempt to hit two intervals for the routes to be maintained respectively, and the implementation is as follows: (11a) The requesting node calculates k indexes for the routes in the set of routes to be maintained using the Bloom filter, and maps the k indexes to the active interval and the inactive interval of the route reply message respectively; (11b) Determine whether the bit positions corresponding to the k indexes in the active interval are all true: If all k bit positions in the active interval are true, it means that this route hits the active interval; Otherwise, it means that this route does not hit the active interval; (11c) Determine whether the bit positions corresponding to the k indexes in the active interval are all true: If all k bit positions in the inactive interval are true, it means that this route hits the inactive interval; Otherwise, it means that this route does not hit the inactive interval.

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