Implementation method of hybrid routing protocol based on HWMP

Abstract

The invention discloses an implementation method of a hybrid routing protocol based on HWMP, which relates to the technical field of communication, and comprises the following steps: initializing and broadcasting a routing request message, generating the routing request message by a source node, and setting an initial control parameter; the intermediate node receives and processes the routing request message, screens the received message according to a preset stability criterion, updates the path stability measurement and hop count information of the screened message, and completes forwarding; the target node receives the processed routing request message, comprehensively selects an optimal path according to path stability and hop count, and reversely sends a routing reply message along the path; establishing a data transmission path from the source node to the target node according to the routing reply message, and performing data communication based on the path; and carrying out continuous maintenance on the established data transmission path, including fault detection and repair processing and an optional active maintenance mechanism.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of communication, in particular to a method for implementing a hybrid routing protocol based on HWMP. BACKGROUND

[0002] In the field of wireless mobile ad hoc networks and mesh network technology, the HWMP protocol has been widely studied and applied as a basic routing protocol. However, the traditional HWMP protocol mainly relies on hop count as the core indicator of path selection, lacking effective consideration of the dynamic stability of the link. In the actual high-mobility network environment, the topology relationship between nodes changes frequently, and only using the minimum hop count as the measurement standard often leads to poor robustness of the selected path. Frequent routing interruption and reconstruction process not only increases the control overhead, but also reduces the reliability and real-time performance of data transmission. In addition, the existing protocol lacks a prediction and evaluation mechanism for the future state of the link in the routing discovery phase, and cannot avoid potential unstable links in advance when establishing the path, thereby limiting the further improvement of the overall network performance. Therefore, we propose a method for implementing a hybrid routing protocol based on HWMP. SUMMARY

[0003] To solve the above technical problems, the application is realized by the following technical scheme:

[0004] The application is a method for implementing a hybrid routing protocol based on HWMP, comprising the following steps:

[0005] Step S1: initialization and broadcast of the routing request message, generating a routing request message by the source node and setting the initial control parameters;

[0006] Step S2: the intermediate node receives and processes the routing request message, filters the received message according to the preset stability criterion, updates the path stability metric and hop count information of the filtered message, and completes the forwarding;

[0007] Step S3: the target node receives the processed routing request message, selects the best path according to the path stability and hop count, and sends a routing reply message along the path in the reverse direction;

[0008] Step S4: establishing a data transmission path from the source node to the target node according to the routing reply message, and performing data communication based on the path;

[0009] Step S5: continuously maintaining the established data transmission path, including fault detection and repair processing, and an optional active maintenance mechanism.

[0010] Further, the step S1 includes the following steps:

[0011] Step S11: The source node generates a routing request message, which includes the destination node address, the source node address, the broadcast ID, the sequence number, and the hop number field, and initializes the hop number field to 0;

[0012] Step S12: The routing request message is updated with a minimum stability threshold field and a forwarding node stability field. The minimum stability threshold field is set by the source node according to application requirements, and the forwarding node stability field is initialized to a maximum value.

[0013] Step S13: The source node broadcasts the routing request message within its wireless communication range.

[0014] Furthermore, step S2 includes the following steps:

[0015] Step S21: After the intermediate node receives the routing request message from the neighbor node for the first time, it queries its routing table. If there is a message record with the same source address and broadcast ID, the message is discarded; otherwise, the subsequent steps are executed.

[0016] Step S22: Parse the routing request message and read the minimum stability threshold and the forwarding node stability field value;

[0017] Step S23: Quantify the stability of the current link over a future period of time, decide whether to forward the routing request, and calculate the predicted lifetime of the link between the current intermediate node and the previous hop neighbor node. The calculation formula is as follows:

[0018]

[0019] In the formula, Let d be the predicted remaining lifetime of the link between node i and its previous hop node j. ij Let be the current instantaneous Euclidean distance between node i and node j, r be the wireless communication radius of the node, and ∈ be the distance tolerance threshold, which is used to provide a buffer zone near the communication boundary to prevent misjudgment of the link status due to small distance fluctuations or measurement errors. Let θ be the relative velocity vector between node i and node j. ij Relative velocity vector The angle between the vector and the line vector connecting node i to node j;

[0020] Step S24: Compare the calculated results Compared with the minimum stability threshold in the message, when If the value is less than the minimum stability threshold, discard the routing request message; otherwise, continue with subsequent processing.

[0021] Step S25: Update the forwarding node stability field in the routing request message, setting it to the current field value and... The smaller value in;

[0022] Step S26: Update the hop number field in the routing request message by incrementing the hop number field by 1, and record the information of the previous hop node to establish a reverse path;

[0023] Step S27: The intermediate node broadcasts the updated routing request message within its wireless communication range.

[0024] Furthermore, step S3 includes the following steps:

[0025] Step S31: After receiving the first routing request message, the target node starts a timer with a duration set to the path discovery time.

[0026] Step S32: Before the timer expires, the target node receives and caches all valid routing request packets arriving via different paths. Each packet carries the hop count of its path and the stability information of the forwarding node.

[0027] Step S33: After the timer expires, the target node selects the optimal path from all received routing request packets according to the path selection strategy. The selection strategy is to prioritize the path with the highest stability value of the forwarding node. If the values ​​are the same, the path with the fewest hops is selected.

[0028] Step S34: The target node sends a routing reply message to the source node via unicast along the reverse path of the selected optimal path. The message contains the stability value of the forwarding nodes of the selected path.

[0029] Furthermore, step S4 includes the following steps:

[0030] Step S41: The routing reply message propagates to the source node along the reverse path. After receiving the message, each intermediate node on the path creates or updates a forward route entry to the target node in its routing table, sets the next-hop address to the address of the node that sent the reply message, and records the stability information of the path.

[0031] Step S42: After receiving the routing reply message, the source node confirms that the route to the target node has been successfully established. The stability metric of this route is the stability value of the forwarding node carried in the message.

[0032] Step S43: The node begins transmitting data packets to the target node through this newly established route.

[0033] Furthermore, step S5 includes the following steps:

[0034] Step S51: When the communication link is interrupted, the node that detects the interruption generates a routing error message and sends it to the source node.

[0035] Step S52: After receiving a routing error message, the source node immediately invalidates the corresponding routing entry and decides whether to initiate a new round of route discovery process based on the requirements.

[0036] Step S53: When a node periodically exchanges neighbor maintenance messages, it calculates the predicted lifetime of the link with the critical next-hop neighbor. If the predicted lifespan of a link is lower than the preset warning threshold, the system will proactively initiate local route repair or send a warning message to the source node.

[0037] The present invention has the following beneficial effects:

[0038] 1. This invention introduces a link stability prediction mechanism to quantitatively assess the future lifetime of a link during the routing request forwarding phase and filters links based on a preset minimum stability threshold. This effectively avoids the use of unstable links in highly dynamic networks, significantly improves the robustness and durability of the selected path, reduces the number of route reconstructions and control overhead caused by frequent link interruptions, and thus improves the reliability of data transmission and the overall network performance.

[0039] 2. This invention adopts a path selection strategy that prioritizes stability and prioritizes hop count at the target node. It comprehensively considers the stability of the path and the number of hops, overcoming the limitation of traditional HWMP which only uses the number of hops as a metric. It can select a stable and efficient transmission path from multiple paths, which not only improves the success rate and real-time performance of data transmission, but also optimizes the utilization efficiency of network resources.

[0040] 3. This invention has an active maintenance mechanism. Nodes periodically calculate the predicted lifetime of links with critical neighbors and trigger local repair or send an early warning to the source node when the link stability is lower than the warning threshold. This realizes preventive maintenance of routes, further enhances the network's adaptability and service quality in dynamic environments, and extends the effective lifespan of paths.

[0041] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating an implementation method of a hybrid routing protocol based on HWMP according to the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Please see Figure 1 As shown, this invention provides an implementation method for a hybrid routing protocol based on HWMP, comprising the following steps:

[0046] Step S1: Initialization and broadcasting of routing request messages. The source node generates routing request messages and sets initial control parameters.

[0047] Step S2: The intermediate node receives and processes routing request messages, filters the received messages according to the preset stability criteria, updates the path stability metric and hop count information of the filtered messages, and completes the forwarding.

[0048] Step S3: The target node receives the processed routing request message, selects the best path based on path stability and hop count, and sends a routing reply message in reverse along that path;

[0049] Step S4: Establish a data transmission path from the source node to the target node based on the routing reply message, and perform data communication based on this path;

[0050] Step S5: Continuously maintain the established data transmission path, including fault detection and repair, as well as optional proactive maintenance mechanisms.

[0051] Step S1 includes the following steps:

[0052] Step S11: The source node generates a routing request message, which includes the destination node address, source node address, broadcast ID, sequence number, and hop number field, and initializes the hop number field to 0.

[0053] Step S12: Add a minimum stability threshold field and a forwarding node stability field to the routing request message. The minimum stability threshold field is set by the source node according to the application requirements, and the forwarding node stability field is initialized to a maximum value.

[0054] Step S13: The source node broadcasts a routing request message within its wireless communication range.

[0055] Step S2 includes the following steps:

[0056] Step S21: After the intermediate node receives the routing request message from the neighbor node for the first time, it queries its routing table. If there is a message record with the same source address and broadcast ID, the message is discarded; otherwise, the subsequent steps are executed.

[0057] Step S22: Parse the routing request message and read the minimum stability threshold and the stability field value of the forwarding node.

[0058] Step S23: Quantify the stability of the current link over a future period of time, decide whether to forward the routing request, and calculate the predicted lifetime of the link between the current intermediate node and the previous hop neighbor node. The calculation formula is as follows:

[0059]

[0060] In the formula, Let d be the predicted remaining lifetime of the link between node i and its previous hop node j. ij Let be the current instantaneous Euclidean distance between node i and node j, r be the wireless communication radius of the node, and ∈ be the distance tolerance threshold, which is used to provide a buffer zone near the communication boundary to prevent misjudgment of the link status due to small distance fluctuations or measurement errors. Let θ be the relative velocity vector between node i and node j. ij Relative velocity vector The angle between the vector and the line vector connecting node i to node j;

[0061] Step S24: Compare the calculated results Compared with the minimum stability threshold in the message, when If the value is less than the minimum stability threshold, discard the routing request message; otherwise, continue with subsequent processing.

[0062] Step S25: Update the forwarding node stability field in the routing request message, setting it to the current field value and... The smaller value in;

[0063] Step S26: Update the hop number field in the routing request message by incrementing the hop number field by 1, and record the information of the previous hop node to establish a reverse path;

[0064] Step S27: The intermediate node broadcasts the updated routing request message within its wireless communication range.

[0065] Step S3 includes the following steps:

[0066] Step S31: After receiving the first routing request message, the target node starts a timer with a duration set to the path discovery time.

[0067] Step S32: Before the timer expires, the target node receives and caches all valid routing request packets arriving via different paths. Each packet carries the hop count of its path and the stability information of the forwarding node.

[0068] Step S33: After the timer expires, the target node selects the optimal path from all received routing request packets according to the path selection strategy. The selection strategy is to prioritize the path with the highest stability value of the forwarding node. If the values ​​are the same, the path with the fewest hops is selected.

[0069] Step S34: The target node sends a routing reply message to the source node via unicast along the reverse path of the selected optimal path. The message contains the stability value of the forwarding nodes of the selected path.

[0070] Step S4 includes the following steps:

[0071] Step S41: The routing reply message propagates to the source node along the reverse path. After receiving the message, each intermediate node on the path creates or updates a forward route entry to the target node in its routing table, sets the next-hop address to the address of the node that sent the reply message, and records the stability information of the path.

[0072] Step S42: After receiving the routing reply message, the source node confirms that the route to the target node has been successfully established. The stability metric of this route is the stability value of the forwarding node carried in the message.

[0073] Step S43: The node begins transmitting data packets to the target node through this newly established route.

[0074] Step S5 includes the following steps:

[0075] Step S51: When the communication link is interrupted, the node that detects the interruption generates a routing error message and sends it to the source node.

[0076] Step S52: After receiving a routing error message, the source node immediately invalidates the corresponding routing entry and decides whether to initiate a new round of route discovery process based on the requirements.

[0077] Step S53: When a node periodically exchanges neighbor maintenance messages, it calculates the predicted lifetime of the link with the critical next-hop neighbor. If the predicted lifespan of a link is lower than the preset warning threshold, the system will proactively initiate local route repair or send a warning message to the source node.

[0078] One specific application of this embodiment is:

[0079] Implementation scenario:

[0080] This embodiment applies to a vehicular ad hoc network (VANET) environment, where vehicles act as mobile nodes and interact with data via wireless communication. In this scenario, the nodes (vehicles) move quickly, the topology changes frequently, and the stability and real-time performance of the routing protocol are critical. In this embodiment, the source node is vehicle A (which needs to transmit real-time traffic data to the target node), the target node is vehicle D, and intermediate nodes include vehicles B and C. The wireless communication radius of each node is 200 meters, the distance tolerance threshold is set to 5 meters, the path discovery time is set to 1 second, and the warning threshold is set to 4 seconds.

[0081] Implementation steps:

[0082] Step 1:

[0083] 1. Source node vehicle A generates a routing request message, which includes the destination node address (the MAC address of vehicle D), the source node address (the MAC address of vehicle A), the broadcast ID (set to 001), the sequence number (set to 1001), and initializes the hop number field to 0.

[0084] 2. Vehicle A adds a minimum stability threshold field and a forwarding node stability field to its routing request message. Based on the reliability requirements of real-time traffic data transmission, the minimum stability threshold is set to 5 seconds; the forwarding node stability field is initialized to a maximum value (set to 100 seconds).

[0085] 3. Vehicle A broadcasts the routing request message within its 200-meter wireless communication range, and vehicle B (150 meters away from A) receives the message.

[0086] Step Two:

[0087] 1. After receiving the routing request message for the first time, intermediate node vehicle B queries its local routing table and finds no message record with the same source address (vehicle A) and broadcast ID (001), and then proceeds to the next steps;

[0088] 2. Vehicle B parses the message and reads that the minimum stability threshold is 5 seconds and the stability field value of the forwarding node is 100 seconds;

[0089] 3. Vehicle B calculates the predicted lifetime of the link between itself and its previous hop (Vehicle A). The instantaneous Euclidean distance d is measured. ij = 150 meters, relative velocity vector ||v ij || = 10 m / s, the angle θ between the relative velocity vector and the vector of the line connecting them. ij =30°, time interval Δt = 1s. Substitute into the formula to calculate:

[0090]

[0091] 4. Comparison The minimum stability threshold of 5 seconds is used. Since 8 seconds > 5 seconds, further processing continues.

[0092] 5. Update the forwarding node stability field to the current field value (100 seconds) and... The smaller of (8 seconds), i.e., 8 seconds;

[0093] 6. Update the jump number segment from 0 to 1, and record the previous jump node as vehicle A, and establish the reverse path;

[0094] 7. Vehicle B broadcasts an updated route request message within its wireless communication range, and Vehicle C (120 meters away from B) and Vehicle D (180 meters away from B) receive the message.

[0095] Step 3:

[0096] 1. After receiving the first routing request message from vehicle B, the target node vehicle D starts a timer with a duration of 1 second (path discovery time).

[0097] 2. Before the timer expires, vehicle D only receives a routing request message from vehicle B (hop count 1, forwarding node stability 8 seconds) and a routing request message from vehicle C (hop count 2, forwarding node stability 6 seconds).

[0098] 3. After the timer expires, vehicle D will prioritize the path with the highest stability value of the forwarding node according to the path selection strategy, i.e., vehicle A → vehicle B → vehicle D (stability 8 seconds, hop count 1).

[0099] 4. Vehicle D sends a routing reply message via unicast along the reverse path (Vehicle D → Vehicle B → Vehicle A). The message contains the stability value of the forwarding node of the selected path, which is 8 seconds.

[0100] Step Four:

[0101] 1. The route reply message first arrives at vehicle B. Vehicle B creates a forward route entry to the destination node D in its routing table, sets the next hop address to the address of vehicle D, and records the path stability as 8 seconds. Then, vehicle B forwards the message to vehicle A.

[0102] 2. After receiving the routing reply message, source node vehicle A confirms that the route to vehicle D has been successfully established, and the stability metric for this route is 8 seconds.

[0103] 3. Vehicle A begins transmitting real-time traffic data to vehicle D via this route. The data transmission rate is stable with no packet loss.

[0104] Step 5:

[0105] 1. After 30 seconds, the link between vehicle B and vehicle D is interrupted due to relative movement. After detecting the interruption, vehicle B generates a routing error message and sends it to the source node vehicle A.

[0106] 2. After receiving the routing error message, vehicle A immediately marks the route entry from vehicle A to vehicle B to vehicle D as invalid and initiates a new round of route discovery.

[0107] 3. In the newly established path (vehicle A → vehicle C → vehicle D) discovered in the latest round of route discovery, vehicle C periodically (every 5 seconds) calculates its connection to the next hop vehicle D. When a certain calculation yields When the time is less than 4 seconds (below the warning threshold), vehicle C actively sends a warning message to vehicle A, and vehicle A initiates a backup path switch in advance to avoid data transmission interruption.

[0108] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0109] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for implementing a hybrid routing protocol based on HWMP, characterized in that: Includes the following steps: Step S1: Initialization and broadcasting of routing request messages. The source node generates routing request messages and sets initial control parameters. Step S2: The intermediate node receives and processes routing request messages, filters the received messages according to the preset stability criteria, updates the path stability metric and hop count information of the filtered messages, and completes the forwarding. Step S3: The target node receives the processed routing request message, selects the best path based on path stability and hop count, and sends a routing reply message in reverse along that path; Step S4: Establish a data transmission path from the source node to the target node based on the routing reply message, and perform data communication based on this path; Step S5: Continuously maintain the established data transmission path, including fault detection and repair, as well as optional proactive maintenance mechanisms.

2. The implementation method of a hybrid routing protocol based on HWMP according to claim 1, characterized in that, Step S1 includes the following steps: Step S11: The source node generates a routing request message, which includes the destination node address, the source node address, the broadcast ID, the sequence number, and the hop number field, and initializes the hop number field to 0; Step S12: The routing request message is updated with a minimum stability threshold field and a forwarding node stability field. The minimum stability threshold field is set by the source node according to application requirements, and the forwarding node stability field is initialized to a maximum value. Step S13: The source node broadcasts the routing request message within its wireless communication range.

3. The implementation method of a hybrid routing protocol based on HWMP according to claim 1, characterized in that, Step S2 includes the following steps: Step S21: After the intermediate node receives the routing request message from the neighbor node for the first time, it queries its routing table. If there is a message record with the same source address and broadcast ID, the message is discarded; otherwise, the subsequent steps are executed. Step S22: Parse the routing request message and read the minimum stability threshold and the forwarding node stability field value. Step S23: Quantify the stability of the current link over a future period of time, decide whether to forward the routing request, and calculate the predicted lifetime of the link between the current intermediate node and the previous hop neighbor node. The calculation formula is as follows: In the formula, Let d be the predicted remaining lifetime of the link between node i and its previous hop node j. ij Let be the current instantaneous Euclidean distance between node i and node j, r be the wireless communication radius of the node, and ∈ be the distance tolerance threshold, which is used to provide a buffer zone near the communication boundary to prevent misjudgment of the link status due to small distance fluctuations or measurement errors. Let θ be the relative velocity vector between node i and node j. ij Relative velocity vector The angle between the vector of the line connecting node i and node j; Step S24: Compare the calculated results Compared with the minimum stability threshold in the message, when If the value is less than the minimum stability threshold, discard the routing request message; otherwise, continue with subsequent processing. Step S25: Update the forwarding node stability field in the routing request message, setting it to the current field value and... The smaller value in; Step S26: Update the hop number field in the routing request message by incrementing the hop number field by 1, and record the information of the previous hop node to establish a reverse path; Step S27: The intermediate node broadcasts the updated routing request message within its wireless communication range.

4. The implementation method of a hybrid routing protocol based on HWMP according to claim 1, characterized in that, Step S3 includes the following steps: Step S31: After receiving the first routing request message, the target node starts a timer with a duration set to the path discovery time. Step S32: Before the timer expires, the target node receives and caches all valid routing request packets arriving via different paths. Each packet carries the hop count of its path and the stability information of the forwarding node. Step S33: After the timer expires, the target node selects the optimal path from all received routing request packets according to the path selection strategy. The selection strategy is to prioritize the path with the highest stability value of the forwarding node. If the values ​​are the same, the path with the fewest hops is selected. Step S34: The target node sends a routing reply message to the source node via unicast along the reverse path of the selected optimal path. The message contains the stability value of the forwarding nodes of the selected path.

5. The implementation method of a hybrid routing protocol based on HWMP according to claim 1, characterized in that, Step S4 includes the following steps: Step S41: The routing reply message propagates to the source node along the reverse path. After receiving the message, each intermediate node on the path creates or updates a forward route entry to the target node in its routing table, sets the next-hop address to the address of the node that sent the reply message, and records the stability information of the path. Step S42: After receiving the routing reply message, the source node confirms that the route to the target node has been successfully established. The stability metric of this route is the stability value of the forwarding node carried in the message. Step S43: The node begins transmitting data packets to the target node through this newly established route.

6. The implementation method of a hybrid routing protocol based on HWMP according to claim 1, characterized in that, Step S5 includes the following steps: Step S51: When the communication link is interrupted, the node that detects the interruption generates a routing error message and sends it to the source node. Step S52: After receiving a routing error message, the source node immediately invalidates the corresponding routing entry and decides whether to initiate a new round of route discovery process based on the requirements. Step S53: When a node periodically exchanges neighbor maintenance messages, it calculates the predicted lifetime of the link with the critical next-hop neighbor. If the predicted lifespan of a link is lower than the preset warning threshold, the system will proactively initiate local route repair or send a warning message to the source node.

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