Method, device and equipment for detecting dynamic network withdrawal in wireless ad hoc network

Abstract

This invention relates to a method, apparatus, and device for dynamic network exit detection in wireless ad hoc networks, belonging to the field of wireless communication technology. The method includes: performing TDMA time slot partitioning on the wireless ad hoc network; online nodes reusing NET frames from network synchronization time slots to perform neighbor node activity status monitoring and generate a neighbor activity table; for each NET frame received, the node updates the active timestamp and clears the corresponding neighbor node's loss count; traversing the node information in the neighbor activity table at a preset period, marking nodes that have not updated their active timestamps within a timeout as suspected exit nodes, sending probe frames to the suspected exit nodes and obtaining the corresponding probe response results; determining based on the probe response results, confirming the suspected exit node's exit if no response is received, performing a removal operation and a logical ID recycling operation for the suspected exit node, and updating the local routing table accordingly. This invention can quickly detect node exits without additional signaling, reducing channel occupancy and shortening route convergence time.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a method, apparatus, and device for detecting dynamic network decommissioning of wireless ad hoc networks. Background Technology

[0002] In ad hoc networks, nodes maintain neighbor relationships by periodically broadcasting Hello messages or beacon frames: nodes periodically broadcast Hello messages to their neighbors and record the last active time of each neighbor. If a node fails to receive a message from a neighbor multiple times consecutively, it is considered offline, triggering a route update. Furthermore, in centralized or semi-centralized networks, the master node periodically broadcasts beacon frames containing a list of all nodes in the network, and slave nodes determine the network status based on the reception of these beacon frames.

[0003] However, the aforementioned existing technologies have significant shortcomings in practical applications. On the one hand, neighbor detection based on Hello messages requires nodes to periodically send additional signaling, consuming limited wireless channel resources, and the detection latency is strongly correlated with the Hello period, making it difficult to achieve rapid response with low overhead. In master-slave networks, simply relying on the master node to broadcast beacon frames cannot effectively distinguish whether a node actively leaves the network or experiences a temporary signal interruption. On the other hand, when a node leaves the network, updates to existing routing protocols rely on additional signaling interactions, resulting in a long convergence time. This causes data packets to continue attempting to be sent to the invalidated routes for several periods after the node leaves the network. Simultaneously, there is a lack of fault tolerance mechanisms for data in transit; once a node leaves the network, fragmented data cannot be reassembled, leading to data loss. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, and device for dynamic network decommissioning detection of wireless ad hoc networks that can achieve rapid detection of node decommissioning and data transmission fault tolerance based on the reuse of existing signaling frames, in order to address the above-mentioned technical problems.

[0005] A method for dynamic network decommissioning detection in a wireless ad hoc network, the method comprising: TDMA time slots are divided for the wireless ad hoc network. Online nodes reuse NET frames of the network synchronization time slot to perform neighbor node activity status monitoring and generate a neighbor activity table containing neighbor node activity timestamps and loss counts. Each time a node receives a NET frame, it updates the active timestamp of the corresponding neighbor node in the neighbor activity table and clears the loss count of the corresponding neighbor node. The node information in the neighbor activity table is traversed according to a preset period. Nodes that have not updated their active timestamps after timeout are marked as suspected de-network nodes. Probe frames are sent to the suspected de-network nodes and the corresponding probe response results are obtained. Based on the detection response results, if no response is received, it is confirmed that the suspected de-network node has de-networked. The removal operation of the suspected de-network node and the recycling operation of the logical ID are performed, and the local routing table is updated accordingly.

[0006] On the other hand, a wireless self-organizing network dynamic decommissioning detection device is also provided, comprising: The time slot configuration and neighbor monitoring module is used to perform TDMA time slot allocation for the wireless ad hoc network; the NET frames of the network synchronization time slots of the online node multiplex the neighbor node activity status monitoring and generate a neighbor activity table containing the neighbor node activity timestamps and loss counts; The NET frame processing and active update module is used to update the active timestamp of the corresponding neighbor node in the neighbor active table and clear the loss count of the corresponding neighbor node for each NET frame received by the node. The periodic traversal and suspected node determination module is used to traverse the node information in the neighbor activity table according to a preset period, mark the nodes that have not updated their active timestamps after timeout as suspected nodes that have left the network, send probe frames to the suspected nodes that have left the network, and obtain the corresponding probe response results. The network exit confirmation and resource reclamation module is used to determine the exit based on the detection response result. If no response is received, the module confirms that the suspected network exit node has exited the network, performs the removal operation of the suspected network exit node and the reclamation operation of the logical ID, and updates the local routing table accordingly.

[0007] On the other hand, a computer device is also provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the above-mentioned wireless ad hoc network dynamic decommissioning detection method.

[0008] Compared with existing technologies, the wireless ad hoc network dynamic decommissioning detection method, apparatus, and device provided by this invention have the following beneficial effects: 1. NET frames that reuse network synchronization time slots are used to perform neighbor node activity monitoring without the need to periodically send Hello messages or heartbeat frames, thus avoiding the occupation of wireless channel resources by additional signaling. This is especially suitable for self-organizing network scenarios with dense nodes.

[0009] 2. By traversing the neighbor activity table at a preset period and combining it with a loss counting mechanism, suspicious disconnected nodes can be quickly identified within the preset period. Compared with the existing detection scheme based on the Hello period, the detection speed is significantly improved.

[0010] 3. By adopting the method of marking suspected nodes and sending probe frames for confirmation after a timeout without updating, the system avoids single misjudgments caused by temporary signal interruption or interference, thus improving the accuracy of network exit detection.

[0011] 4. Once a node is confirmed to be decommissioned, the node removal, logical ID recycling, and local routing table update are performed immediately without waiting for the routing protocol to rediscover, shortening the window period for data packets to be sent to the failed route and improving network transmission efficiency. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention, and those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart illustrating a method for dynamic network exit detection in a wireless ad hoc network in one embodiment; Figure 2 This is a structural block diagram of a wireless ad hoc network dynamic decommissioning detection device in one embodiment; Figure 3 This is an internal structural diagram of a computer device in one embodiment.

[0014] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0015] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0016] It is understood that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0017] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0018] Example 1 like Figure 1 As shown, a method for dynamic network decommissioning detection in a wireless ad hoc network is provided, including the following steps: Step 201: Perform TDMA time slot division on the wireless ad hoc network. Online nodes reuse NET frames of network synchronization time slots to perform neighbor node activity status monitoring and generate a neighbor activity table containing neighbor node activity timestamps and loss counts.

[0019] Step 202: For each NET frame received, the node updates the active timestamp of the corresponding neighbor node in the neighbor active table and clears the loss count of the corresponding neighbor node.

[0020] Step 203: Traverse the node information in the neighbor active table according to the preset period, mark the nodes that have not updated their active timestamps after the timeout as suspected de-network nodes, send probe frames to the suspected de-network nodes and obtain the corresponding probe response results.

[0021] Step 204: Based on the detection response results, determine whether the suspected decommissioned node has decommissioned. If no response is received, confirm that the suspected decommissioned node has decommissioned and perform the removal operation of the suspected decommissioned node, the recycling operation of the logical ID, and update the local routing table accordingly.

[0022] In the aforementioned dynamic decommissioning detection method for wireless ad hoc networks, neighbor node activity monitoring is performed by dividing the wireless ad hoc network into TDMA time slots and reusing NET frames of network synchronization time slots. This eliminates the need to send additional Hello messages or heartbeat signaling, effectively reducing the signaling overhead of the wireless channel and avoiding channel congestion in large-scale node scenarios. Relying on a neighbor activity table containing active timestamps and loss counts, periodic traversal and timeout determination are performed, coupled with a probe frame confirmation mechanism, enabling rapid and accurate detection of node decommissioning with low resource consumption and shortening offline node identification latency. After confirming node decommissioning, node removal, logical ID recycling, and local routing table updates are performed simultaneously, without relying on additional routing protocol signaling interactions, significantly shortening route convergence time and preventing continuous transmission of data packets to failed routes. This also provides fundamental support for data transmission fault tolerance. From the perspectives of node management, route maintenance, and resource reuse, this method addresses the technical problems of high signaling overhead, high detection latency, slow route convergence, and poor transmission reliability in existing technologies.

[0023] In the specific implementation of step 201, TDMA (Time Division Multiple Access) time slot allocation divides a single network cycle of a wireless ad hoc network into multiple time slots with fixed functions. Each time slot sequentially undertakes different network interaction tasks. The time slot types include BBSC (Broadcast Time Slot), RAC (Response Time Slot), ACK (Data Acknowledgment Time Slot), NET (Network Synchronization Time Slot), DATA (Data Transmission Time Slot), and DATA_ACK (Data Acknowledgment Time Slot). The network operation mode is divided into two types: fast wave mode and slow wave mode. The number of DATA time slots is adaptively adjusted in different modes.

[0024] After completing time slot synchronization, the node will complete the transition between power-on, network access, and working states according to a preset state machine. This invention defines the node as having four working states: initial state (INITIAL_STATE), connected state (CONNECT_STATE), online state (ONLINE_STATE), and transmission state (TRANS_STATE). The switching process and execution logic of each state are as follows: After power-on, the node directly enters the initial state. In this state, it continuously listens for physical layer interrupts and waits to receive BBSC frames (broadcast frames). If a valid BBSC frame is received and there is an available logical ID in the network, it assigns a logical ID to itself and transitions from the initial state to the connected state. If a timeout interrupt is received and there are no other online nodes in the network, it upgrades itself to a master node and directly transitions from the initial state to the online state.

[0025] When a node is in the connected state, it has completed the transmission of the RAC frame (response frame) and is waiting for the ACK frame (acknowledgment frame) response. If an ACK frame is received and the target ID in the frame matches its own logical ID, the node is determined to have successfully joined the network and transitions from the connected state to the online state. If no ACK frame is received within the specified time slot window, the node is determined to have timed out and returns to the initial state from the connected state.

[0026] After completing network access, a node enters the online state. In this state, the node participates in network communication normally, continuously monitors for various types of physical layer interruptions, and can independently initiate data transmission or forward service data from other nodes. When a BBSC frame is received, the node updates its active time and maintains neighbor relationships. When a NET frame is received, the node updates the network topology and synchronizes global routing information. When a RAC frame is received, the node processes the network access response or data forwarding response according to the request type within the frame.

[0027] When a node initiates or receives data transmission, it transitions from the online state to the transmission state. In the transmission state, the node receives data fragments and records the reception status of each data fragment through the data_ok array in the data status record structure. After receiving all data fragments completely, the node sends a DATA_ACK frame to complete the confirmation and returns from the transmission state to the online state. If the transmission fails, the retransmission mechanism is triggered directly to ensure the reliability of data transmission.

[0028] A node can only perform neighbor node activity monitoring after completing the above state transition process and entering the online state. After joining the network, a node is in the online state by default. In this state, the node can participate in network communication and maintain neighbor relationships and routing information normally.

[0029] The NET time slot is a dedicated time slot for broadcasting network status synchronization information. Online nodes do not need to periodically send Hello messages or heartbeat frames or other additional signaling; they can simply reuse the NET frames broadcast within this time slot to collect and monitor the activity status of neighboring nodes, thereby reducing the signaling overhead of the wireless channel at its source. Specifically: within the NET time slot of the TDMA time slot, a node reuses and receives NET frames broadcast by other online nodes; it parses the source node logical ID carried in the NET frame and uses the source node logical ID as an index to match the corresponding record in the neighbor activity table; based on the matched record, it performs real-time updates of the neighbor node activity status; and it stores the updated status data in the neighbor activity table, completing this round of activity status monitoring.

[0030] The Neighbor Activity Table is a global node status record table maintained locally by online nodes. Each record in the table corresponds to an online node in the network. The record fields include the node logical ID, the neighbor node activity timestamp, and the loss count. The activity timestamp is used to mark the time when the node was last detected as active, and the loss count is used to count the number of consecutive periods during which the node was not detected as active.

[0031] The active timestamp is generated by reading the value of the node's hardware cycle counter, which automatically increments with the network cycle and can accurately reflect the timing information of network operation.

[0032] Preferably, the specific division rules for TDMA time slots are as follows: time slot 0 is the BBSC time slot, used to broadcast the available ID of the node and its neighbor relationship; time slots 1 to 6 are the RAC time slots, used to respond to network access requests or data forwarding requests; time slot 7 is the ACK time slot, used to send an acknowledgment response for network access completion or data reception; time slot 8 is the NET time slot, used to broadcast network status synchronization information; in fast wave mode, time slots 9 to 18 are the DATA time slots, and time slot 19 is the DATA_ACK time slot; in slow wave mode, time slots 9 to 10 are the DATA time slots, and time slot 11 is the DATA_ACK time slot.

[0033] This step achieves node status collection without additional signaling overhead through standardized TDMA time slot allocation and NET frame reuse monitoring, providing basic data support for subsequent network decommissioning detection.

[0034] In the specific implementation of step 202, the NET frame is the core frame structure broadcast within the NET time slot. The frame carries the logical ID information of the source node, used to identify the node sending the NET frame. When a node is in ONLINE_STATE, it listens for and receives NET frames broadcast by other online nodes in the NET time slot of each network cycle. Upon successfully receiving a NET frame, it parses the source node's logical ID within the frame and uses this logical ID as an index to match the corresponding node record in the neighbor active table.

[0035] Upon successful matching, the node reads the current count value from the hardware cycle counter, uses this current count value as the latest active timestamp, overwrites the original active timestamp of the node in the neighbor active table, and resets the corresponding loss count of the node to zero, completing a single round of active status update. If the node does not receive a NET frame from a neighbor node, it does not perform the operation of updating the active timestamp of that neighbor node or clearing the loss count.

[0036] This step utilizes a real-time update mechanism triggered by NET frame reception to ensure that the neighbor activity table reflects the latest activity status of each neighbor node in real time. By updating the active timestamp and resetting the loss count for each received NET frame, it is possible to accurately distinguish between normally active nodes and potentially offline nodes, providing precise data for timeout determination and network exit detection.

[0037] In the specific implementation of step 203, the preset period is a single network cycle of the wireless ad hoc network. At the end of each network cycle, the node automatically triggers the traversal operation of the neighbor activity table without manual intervention.

[0038] At the end of each network cycle, the node traverses the neighbor activity table, reads the value of the current hardware cycle counter as the current timestamp, calculates the difference between the current timestamp and the active timestamps of each node in the neighbor activity table, and uses this difference to determine whether the node has timed out and failed to update its activity status.

[0039] The timeout threshold is determined based on the network cycle of the wireless ad hoc network. Specifically, it reads the current network operating time slot mode; when the network is in fast wave mode, the timeout threshold is set to the first number of cycles; when the network is in slow wave mode, the timeout threshold is set to the second number of cycles; wherein the first number of cycles is less than the second number of cycles. Preferably, the timeout threshold is set to 3 network cycles in fast wave mode and 15 network cycles in slow wave mode.

[0040] If the calculated difference exceeds the preset timeout threshold, the loss count of the node is increased by one step value; if the difference does not exceed the preset timeout threshold, the loss count of the node is cleared to zero; the increased or cleared loss count is written back to the loss count field corresponding to the node in the neighbor active table.

[0041] When the cumulative number of lost nodes reaches the preset maximum number of lost nodes, the step of marking them as suspected nodes to be decommissioned is executed. Preferably, the preset maximum number of lost nodes is 3.

[0042] After marking a suspected de-network node, the node sends a probe request frame to the suspected de-network node via network frames. Within a preset waiting time, it listens for and obtains the probe response results returned by the suspected de-network node. The probe confirmation mechanism avoids misjudgment caused by temporary signal interruption or environmental interference.

[0043] This step employs a multi-level decision-making logic involving periodic traversal, difference calculation, loss count accumulation, and detection confirmation, which improves the accuracy of network exit determination while ensuring detection speed.

[0044] In the specific implementation of step 204, the node judges the detection response result. If no response frame is received from the suspected de-network node within the preset waiting time, the suspected de-network node is confirmed to have officially de-networked. If a valid response frame is received, the node is determined to be temporarily interrupted, its loss count is reset and the node status is retained.

[0045] After confirming that a node is decommissioned, the following operations are executed in sequence: node removal, logical ID reclamation, data buffer cleanup, and routing table update.

[0046] The node removal operation deletes the node from the local global node table and terminates the node's network interaction permissions.

[0047] The logical ID recycling operation is as follows: after confirming that a node has left the network, extract the logical ID corresponding to the node; mark the bit corresponding to the logical ID in the available ID bitmap from occupied to idle; and broadcast the updated available ID bitmap to the entire network in the BBSC time slot of the TDMA time slot to realize the dynamic reuse of logical ID resources.

[0048] Before updating the local routing table, a data buffer preprocessing step must be performed. Specifically, all local data buffers to be sent are traversed. Each buffer corresponds to a data packet to be sent, and the routing path of each data packet is stored in the form of a sequence of logical IDs of nodes, forming a routing path sequence. It is checked whether the routing path sequence contains the logical ID of a node that has been confirmed to have left the network. If it does, the buffer corresponding to the data packet is cleared, and a transmission failure event is reported to the upper-layer protocol stack. If it does not, the buffer corresponding to the data packet is retained, waiting for transmission in the next cycle. Based on the cleaned data buffers, the network topology is updated according to the removal operation of the decommissioned nodes, and the routing paths affected by the decommissioned nodes in the local routing table are recalculated. This eliminates the need to wait for the routing protocol to re-initiate route discovery, shortening the route convergence time.

[0049] In one embodiment, when a suspected network-decommissioned node is confirmed to have left the network, fault-tolerant transmission is performed on the service data whose transmission was interrupted due to the network decommissioning. Specifically, the sending end dynamically fragments the service data to be transmitted according to the current network time slot mode, and sends each fragment in the order of data transmission time slots. Preferably, in fast wave mode, the service data is divided into 5 fragments, occupying 10 data time slots for transmission, with each pair of fragments occupying one data time slot; in slow wave mode, the service data is divided into 2 fragments, occupying 2 data time slots for transmission, with each fragment occupying one data time slot.

[0050] The receiving end maintains a data status record structure and updates the reception status of the corresponding fragment in the data status record structure according to the actual received fragment data. The data status record structure is a boolean array, the length of which is equal to the number of service data fragments in the current network mode. During initialization, all elements of the array are assigned the value of "not received" (false).

[0051] Each time the receiving end successfully receives a data fragment, it updates the element at the corresponding position in the array to the received status (true) according to the fragment's sequence number in the data packet.

[0052] After a single round of service transmission ends, the receiving end verifies the integrity of the fragmented data based on the data status record structure. If all elements in the array are in the received state, the fragmented data is considered complete, and a success flag (0xAA) is sent back to the sending end within the data confirmation time slot. If any element is in the unreceived state, the fragmented data is considered incomplete, and a failure flag (0xFF) is sent back to the sending end within the data confirmation time slot.

[0053] Upon receiving a failure flag, the sending end activates a backup time slot to perform fragmented retransmission. If the receiving end reports a success flag after retransmission, the current transmission ends; otherwise, it is marked as a transmission failure. It's worth noting that the backup time slot is the second set of data time slots pre-set within the current network cycle, and its number is the same as the first set. This fault-tolerance mechanism ensures the complete transmission of service data even in abnormal situations such as node disconnection.

[0054] Furthermore, this method establishes a collaborative processing mechanism between physical layer interrupts and the application layer state machine. The application layer continuously monitors the physical layer for BBSC (Broadcast Slot Interrupt), RAC (Response Slot Interrupt), ACK (Data Acknowledgment Slot Interrupt), NET (Network Synchronization Slot Interrupt), DATA (Data Transmission Slot Interrupt), DATA_ACK (Data Acknowledgment Slot Interrupt), and error frame interrupts. Based on the node's current initial state, connection state, online state, or transmission state (TRANS_STATE), the interrupt is distributed to the corresponding processing function. After processing, the interrupt is cleared, achieving efficient event-driven response. Specifically, if the state is initial, network access monitoring or master node initialization is performed based on the interrupt type; if the state is connected, ACK waiting or BBSC re-entry is performed based on the interrupt type; if the state is online, corresponding network maintenance or data response is performed based on the interrupt type; and if the state is transmission, data reception or acknowledgment processing is performed based on the interrupt type.

[0055] This step, through an integrated post-network decommissioning process, enables rapid recovery of node resources, fast route convergence, and reliable data transmission, comprehensively resolving the problems of high signaling overhead, high detection latency, slow route convergence, and easy data loss in existing technologies.

[0056] It should be understood that, although this embodiment Figure 1 The steps are shown sequentially as indicated by the arrows, but they are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order in which these steps are performed; they can be executed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0057] Example 2 Based on the dynamic network decommissioning detection method for wireless ad hoc networks in Embodiment 1, this embodiment discloses a dynamic network decommissioning detection device for wireless ad hoc networks, such as... Figure 3 As shown, the wireless ad hoc network dynamic decommissioning detection device includes: a time slot configuration and neighbor monitoring module 401, a NET frame processing and active update module 402, a periodic traversal and suspected case determination module 403, and a decommissioning confirmation and resource reclamation module 404, wherein: The time slot configuration and neighbor monitoring module 401 is used to perform TDMA time slot allocation for the wireless ad hoc network; the online node reuses the NET frame of the network synchronization time slot to perform neighbor node activity status monitoring and generate a neighbor activity table containing neighbor node activity timestamps and loss counts.

[0058] The NET frame processing and active update module 402 is used to update the active timestamp of the corresponding neighbor node in the neighbor active table and clear the loss count of the corresponding neighbor node for each NET frame received by the node.

[0059] The periodic traversal and suspected node determination module 403 is used to traverse the node information in the neighbor active table according to a preset period, mark the nodes that have not updated their active timestamps after the timeout as suspected de-network nodes, send probe frames to the suspected de-network nodes and obtain the corresponding probe response results.

[0060] The network exit confirmation and resource reclamation module 404 is used to make a judgment based on the detection response results. If no response is received, it confirms that the suspected network exit node has exited the network, performs the removal operation of the suspected network exit node and the reclamation operation of the logical ID, and updates the local routing table in conjunction with the operation.

[0061] In this embodiment, the specific working process and working principle of the time slot configuration and neighbor monitoring module 401, the NET frame processing and active update module 402, the periodic traversal and suspected judgment module 403, and the network decommissioning confirmation and resource reclamation module 404 are the same as those in Embodiment 1, and therefore will not be described again in this embodiment. Each unit module can be implemented entirely or partially through software, hardware, or a combination thereof. Each unit module can be embedded in or independent of the processor in the computer device in hardware form, or it can be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above unit modules.

[0062] Example 3 like Figure 3 The diagram illustrates a computer device disclosed in this embodiment, including a transmitter, a receiver, a memory, and a processor. The transmitter is used to send instructions and data, the receiver is used to receive instructions and data, the memory is used to store computer execution instructions, and the processor is used to execute the computer execution instructions stored in the memory to implement the method in Embodiment 1 above.

[0063] It is important to note that the aforementioned memory can be either standalone or integrated with the processor. When the memory is set up independently, the terminal device also includes a bus for connecting the memory and the processor.

[0064] Example 4 This embodiment discloses a computer-readable storage medium storing computer-executable instructions. When a processor executes the computer-executable instructions, it implements the method in Embodiment 1 above.

[0065] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0066] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for dynamic network decommissioning detection in a wireless ad hoc network, characterized in that, The method includes: TDMA time slots are divided for the wireless ad hoc network. Online nodes reuse NET frames of the network synchronization time slot to perform neighbor node activity status monitoring and generate a neighbor activity table containing neighbor node activity timestamps and loss counts. Each time a node receives a NET frame, it updates the active timestamp of the corresponding neighbor node in the neighbor activity table and clears the loss count of the corresponding neighbor node. The node information in the neighbor activity table is traversed according to a preset period. Nodes that have not updated their active timestamps after timeout are marked as suspected de-network nodes. Probe frames are sent to the suspected de-network nodes and the corresponding probe response results are obtained. Based on the detection response results, if no response is received, it is confirmed that the suspected de-network node has de-networked. The removal operation of the suspected de-network node and the recycling operation of the logical ID are performed, and the local routing table is updated accordingly.

2. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 1, characterized in that, Once the suspected decommissioned node is confirmed to have decommissioned, fault-tolerant transmission is performed on the service data whose transmission was interrupted due to the decommissioning, including: The sending end dynamically fragments the service data to be transmitted according to the current network timeslot mode, and sends each fragment in the order of data timeslots. The receiving end maintains a data status record structure and updates the receiving status of the corresponding fragment in the data status record structure according to the actual received fragment data; After a single round of service transmission time slot ends, the receiving end verifies the integrity of the fragmented data based on the data status record structure; if the fragmented data is complete, it sends a success flag to the sending end within the data confirmation time slot; if the fragmented data is incomplete, it sends a failure flag to the sending end within the data confirmation time slot. Upon receiving the failure flag, the sending end activates the backup time slot to perform fragmented retransmission; upon receiving the success flag, the current transmission ends.

3. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 1 or 2, characterized in that, Online nodes reuse NET frames from network synchronization time slots to perform neighbor node activity status monitoring, including: During the network synchronization time slot of TDMA, the node multiplexes the NET frames broadcast by other online nodes; Parse the source node logical ID carried in the NET frame, and use the source node logical ID as an index to match the corresponding record in the neighbor active table; Based on the matched records, perform real-time updates of the activity status of neighboring nodes; The updated status data is stored in the neighbor activity table to complete this round of activity status monitoring.

4. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 1 or 2, characterized in that, Before marking nodes that have not updated their active timestamps after a timeout as suspected decommissioning nodes, the following also applies: At the end of each network cycle, the neighbor activity table is traversed, the value of the current cycle counter is read, and the difference is calculated with the active timestamp of each node in the neighbor activity table; If the difference exceeds the preset timeout threshold, the loss count of the node is increased by one step value. If the difference does not exceed the preset timeout threshold, the loss count of the node is cleared to zero. The increased or cleared loss count will be written back to the loss count field corresponding to the node in the neighbor active table; When the cumulative loss count reaches the preset maximum number of losses, the step of marking nodes as suspected decommissioned nodes is executed.

5. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 4, characterized in that, The preset timeout threshold is determined based on the network cycle of the wireless ad hoc network, including: Read the current network time slot pattern; When the network is in fast wave mode, the timeout threshold is set to a first number of cycles; when the network is in slow wave mode, the timeout threshold is set to a second number of cycles; wherein the first number of cycles is less than the second number of cycles.

6. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 1 or 2, characterized in that, The logical ID reclamation operation includes: After confirming that a node has left the network, extract the logical ID corresponding to the node that has left the network; The bits corresponding to the logical IDs in the available ID bitmap are marked from occupied to free. In the preset broadcast time slot within the TDMA time slot, the updated available ID bitmap is broadcast across the entire network.

7. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 6, characterized in that, This will trigger a synchronized update of the local routing table, including: Traverse the locally stored buffers of data to be sent. Each buffer corresponds to a data packet to be sent. The routing path of each data packet is stored in the form of a sequence of logical ID nodes, forming a sequence of routing paths. Check whether the routing path sequence contains the logical ID of a node that has been confirmed to have left the network; If the packet is contained, the buffer corresponding to the packet is cleared, and a transmission failure event is reported to the upper-layer protocol stack; if the packet is not contained, the buffer corresponding to the packet is retained, and the packet is sent in the next cycle. The network topology is updated based on the removal operation of the decommissioned node, and the routing paths affected by the decommissioned node in the local routing table are recalculated.

8. The method for dynamic network decommissioning detection of wireless ad hoc networks according to claim 2, characterized in that, The array length of the data status record structure is equal to the number of fragments of service data in the current network mode; During initialization, all elements of the array are assigned a value indicating that they have not been received. Each time the receiving end successfully receives a data fragment, it updates the element at the corresponding position in the array to the received status according to the sequence number of the fragment in the data packet. After a single round of service transmission time slots ends, the array is traversed. If all elements are in a received state, the fragmented data is determined to be complete; if any element is in a not received state, the fragmented data is determined to be incomplete.

9. A device for detecting dynamic network decommissioning in a wireless self-organizing network, characterized in that, The device includes: The time slot configuration and neighbor monitoring module is used to perform TDMA time slot allocation for the wireless ad hoc network; the NET frames of the network synchronization time slots of the online node multiplex the neighbor node activity status monitoring and generate a neighbor activity table containing the neighbor node activity timestamps and loss counts; The NET frame processing and active update module is used to update the active timestamp of the corresponding neighbor node in the neighbor active table and clear the loss count of the corresponding neighbor node for each NET frame received by the node. The periodic traversal and suspected node determination module is used to traverse the node information in the neighbor activity table according to a preset period, mark the nodes that have not updated their active timestamps after timeout as suspected nodes that have left the network, send probe frames to the suspected nodes that have left the network, and obtain the corresponding probe response results. The network exit confirmation and resource reclamation module is used to determine the exit based on the detection response result. If no response is received, the module confirms that the suspected network exit node has exited the network, performs the removal operation of the suspected network exit node and the reclamation operation of the logical ID, and updates the local routing table accordingly.

10. A computer device, comprising a memory and a processor, characterized in that, The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the wireless ad hoc network dynamic decommissioning detection method according to any one of claims 1 to 8.

Images