CN104125108A - Fault diagnosis device and method thereof and setting method of back-off time - Google Patents

Abstract

Embodiments of the present invention provide a fault diagnosis device and method, and a method for setting back-off time. The fault diagnosis device includes: a time start unit, which starts the back-off time of the diagnostic node for the suspected node when the suspected node needs to be diagnosed; The root node determination unit determines the root node according to the countdown of the back-off time; the root node is the diagnosis node whose back-off time ends first among the plurality of diagnosis nodes of the suspected node; the diagnosis control unit controls the root node The node starts to establish the diagnosis tree, receives the diagnosis information sent by the nodes in the diagnosis tree, and reports the diagnosis result to the gateway. Through the embodiment of the present invention, a unified diagnosis result can be obtained at the gateway, while reducing the communication overhead of the system.

Description

Fault diagnosis device and method, and setting method of backoff time

technical field

The invention relates to the technical field of network fault diagnosis, in particular to a fault diagnosis device and method, and a backoff time setting method.

Background technique

When a fault occurs in the network, it is necessary to start a network fault diagnosis process to eliminate the fault, which may include, for example, link fault diagnosis and node fault diagnosis. At present, when a suspected node needs to be diagnosed, multiple diagnostic nodes of the suspected node may all start the diagnosis process, respectively build a diagnosis tree and report the diagnosis result.

However, in the process of implementing the present invention, the inventor found that the defect of the prior art is: in the case of a suspected node that needs to be diagnosed, it cannot be ensured that only one diagnostic node reports the diagnosis result, so the gateway (GW, Gateway) cannot To obtain a unified diagnosis result, multiple diagnostic processes are started at the same time, and multiple diagnostic nodes report diagnostic information will also bring excessive communication overhead to the system.

Contents of the invention

Embodiments of the present invention provide a fault diagnosis device and method, and a backoff time setting method, aiming at obtaining a unified diagnosis result at a gateway while reducing communication overhead of the system.

According to an aspect of an embodiment of the present invention, a fault diagnosis device is provided, and the fault diagnosis device includes:

A time starting unit, when the suspected node needs to be diagnosed, starts the backoff time of the diagnostic node for the suspected node; wherein, the backoff time is set by dividing a plurality of neighbor nodes of the suspected node into different groups;

The root node determination unit determines the root node according to the countdown of the back-off time; the root node is the diagnostic node whose back-off time ends first among the multiple diagnostic nodes of the suspected node;

The diagnosis control unit controls the root node to start establishing the diagnosis tree, receives the diagnosis information sent by the nodes in the diagnosis tree, and reports the diagnosis result to the gateway.

According to another aspect of the embodiments of the present invention, a fault diagnosis method is provided, and the fault diagnosis method includes:

When the suspected node needs to be diagnosed, start the back-off time of the diagnostic node for the suspected node; wherein, the back-off time is set by dividing a plurality of neighbor nodes of the suspected node into different groups;

Determine the root node according to the countdown to the backoff time; the root node is the diagnostic node whose backoff time ends first among the plurality of diagnostic nodes of the suspect node;

Controlling the root node to start establishing a diagnosis tree, receiving diagnosis information sent by nodes in the diagnosis tree, and reporting a diagnosis result to the gateway.

According to another aspect of the embodiments of the present invention, a backoff time setting method is provided, the setting method comprising:

Divide multiple neighbor nodes of a node into different groups;

For different groups of neighbor nodes, set different backoff time.

The beneficial effects of the embodiments of the present invention are: when a suspected node needs to be diagnosed, start the diagnostic node for the back-off time of the suspected node, determine the root node according to the countdown of the back-off time, and start the establishment of the diagnostic tree by the root node, receive the diagnostic tree The diagnostic information sent by the nodes in the network, and report the diagnostic results to the gateway. In this way, a unified diagnosis result can be obtained at the gateway, while reducing the communication overhead of the system.

With reference to the following description and accompanying drawings, there are disclosed in detail specific embodiments of the invention, indicating the manner in which the principles of the invention may be employed. It should be understood that embodiments of the invention are not limited thereby in scope. Embodiments of the invention encompass many changes, modifications and equivalents within the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment can be used in the same or similar manner in one or more other embodiments, in combination with, or instead of features in other embodiments .

It should be emphasized that the term "comprising/comprising" when used herein refers to the presence of a feature, integer, step or component, but does not exclude the presence or addition of one or more other features, integers, steps or components.

Description of drawings

FIG. 1 is a schematic diagram of the composition of a fault diagnosis device according to Embodiment 1 of the present invention;

Fig. 2 is another schematic diagram of the structure of the fault diagnosis device according to Embodiment 1 of the present invention;

FIG. 3 is a schematic diagram after grouping neighbor nodes of a node according to Embodiment 1 of the present invention;

Fig. 4 is a schematic diagram of the relationship between t ₁ , t ₂ , t ₃ , t ₄ and BO ₁ and BO ₂ in Example 1 of the present invention;

Fig. 5 is another schematic diagram of the structure of the fault diagnosis device according to Embodiment 1 of the present invention;

Fig. 6 is another schematic diagram after grouping neighbor nodes of a node according to Embodiment 1 of the present invention;

Fig. 7 is a schematic structural diagram of a detection package according to Embodiment 1 of the present invention;

FIG. 8 is a schematic flow chart of a fault diagnosis method according to Embodiment 2 of the present invention;

Fig. 9 is another schematic flow chart of the fault diagnosis method in Embodiment 2 of the present invention;

FIG. 10 is a schematic flowchart of a method for setting back-off time in Embodiment 3 of the present invention;

FIG. 11 is an example diagram of a method for setting back-off time in Embodiment 3 of the present invention;

Fig. 12 is another example diagram of the setting method of the backoff time in Embodiment 3 of the present invention;

FIG. 13 is a schematic diagram of a network node according to Embodiment 4 of the present invention;

Fig. 14 is another schematic diagram of a network node according to Embodiment 4 of the present invention.

Detailed ways

Various embodiments of the present invention will be described below in conjunction with the accompanying drawings. These embodiments are illustrative only, and do not limit the present invention. In order to enable those skilled in the art to easily understand the principle and implementation of the present invention, the implementation of the present invention will be described by taking a wireless Ad hoc network or a wireless sensor network as an example. However, it should be noted that the present invention is not limited thereto, and the embodiments of the present invention may be applicable to all communication systems with network faults.

Example 1

An embodiment of the present invention provides a fault diagnosis device, and FIG. 1 is a schematic diagram of the structure of the fault diagnosis device according to the embodiment of the present invention. As shown in FIG. 1 , the fault diagnosis device 100 includes: a time start unit 101 , a root node determination unit 102 and a diagnosis control unit 103 .

Wherein, the time starting unit 101 starts the backoff time of the diagnosis node for the suspected node when the suspected node needs to be diagnosed; the root node determination unit 102 determines the root node according to the countdown to the backoff time, and the root node is a plurality of diagnostics of the suspected node. The diagnosis node whose backoff time ends first among the nodes; the diagnosis control unit 103 controls the root node to start establishing a diagnosis tree, receives the diagnosis information sent by the nodes in the diagnosis tree, and reports the diagnosis result to the gateway.

In this embodiment, the fault diagnosis device 100 may be an integral part of the diagnosis node, and one or more diagnosis nodes in the network may have the fault diagnosis device 100 , and the composition of other parts of the diagnosis node may refer to the prior art. For example, each diagnosis node in the network may have the fault diagnosis device 100; and the suspect node may have the same configuration as the diagnosis node. As a result, a distributed structure can be formed among the various nodes in the network.

But the present invention is not limited thereto. For example, the fault diagnosis device 100 may also be a component independent of the diagnosis node, or a device controlling multiple diagnosis nodes in the network, thereby forming a centralized structure in the network. Alternatively, a part of the fault diagnosis device 100 may be located on a diagnosis node, while another part forms a centralized device. Those skilled in the art can determine the specific implementation scenario according to the actual situation. In the following embodiments, it is only described by taking that the fault diagnosis device is included in one or more diagnosis nodes as an example.

In this embodiment, there may be two kinds of nodes in the diagnosis process: a diagnosis node (DN, Detection Node) and a suspect node (SN, Suspect Node). For example, when node A fails to communicate with node B, node A will suspect that B has failed, and A will start a diagnosis process for B; A is called the diagnosis node DN, and B is called the suspected node SN. A diagnostic node is one or more neighbor nodes of a suspect node, that is, the set of diagnostic nodes can be a subset of the set of neighbor nodes of a suspect node.

When it is suspected that node B needs to be diagnosed, there may be multiple diagnostic nodes (for example, besides node A, there are also nodes C and D). During specific implementation, diagnostic nodes A, C, and D can start the countdown of the backoff time through their respective time starting units 101; Node A is the root node (RN, Root Node), and the root node determination unit 102 in other diagnostic nodes (such as nodes C and D) can determine that nodes C and D are not root nodes (the countdown of the backoff time can be stopped, for details, refer to content described later).

Thus, the diagnostic control unit 103 in the diagnostic node A can perform diagnostic control, and the root node A starts to establish the diagnostic tree, and the nodes added to the diagnostic tree send their own diagnostic information to the root node A, and the node A finally Report the diagnosis result to GW. Therefore, a unified diagnosis result can be obtained at the gateway, and the communication overhead of the system can be reduced at the same time. As for how to establish the diagnosis tree, how to collect the diagnosis information and how to send the diagnosis results, reference may be made to the prior art, which will not be described in detail in the present invention.

In this embodiment, the backoff time can be preset. For a node in the network, backoff time can be set for multiple neighbor nodes of the node. The backoff time can be set by dividing multiple neighbor nodes of the node into different groups, and the neighbor nodes in different groups set different backoff time.

In specific implementation, if there is a gateway node among the neighbor nodes of the suspect node, that is to say, the gateway is a neighbor node of the suspect node, then when the gateway diagnoses the suspect node, the gateway can be determined as the root node. For example, the gateway can be directly determined as the root node, and the diagnostic tree can be established by the gateway; a backoff time shorter than that of other nodes can also be set for the gateway, so that the gateway ends the backoff time first.

In specific implementation, as for how to set the backoff time, the node can uniformly allocate each neighbor node, or each neighbor node can calculate it by itself. The present invention is not limited thereto. In this embodiment, it is only described by taking each neighbor node calculating its own backoff time for the node as an example.

Fig. 2 is another schematic diagram of the structure of the fault diagnosis device according to the embodiment of the present invention. As shown in FIG. 2 , the fault diagnosis device 200 includes: a time start unit 101 , a root node determination unit 102 and a diagnosis control unit 103 . as above.

As shown in FIG. 2 , the fault diagnosis device 200 may further include: a grouping unit 204 . The grouping unit 204 divides multiple neighboring nodes of the suspected node into different groups according to the communication distance.

In a specific implementation, the grouping unit 204 can be specifically used to: divide a plurality of neighbor nodes of a node into a first group and a second group according to the communication distance; wherein, the communication distance between the neighbor nodes in the first group and the node is less than Or equal to a set distance, such as R/2, R/3, R/4, etc., the communication distance between the neighbor nodes in the second group and the node is greater than the set distance. Among them, R is the communication range of the node.

In addition, it is also possible to group by receiving the signal strength of the node, wherein the neighbor nodes in the first group receive the signal strength of the node greater than or equal to the set signal strength threshold, such as -50dBm, -60dBm, -70dBm, etc. , the signal strength received by the neighbor nodes in the first group is less than the set signal strength threshold.

When divided into more than two groups, such as the first group, the second group, and the third group, the communication distance between the neighbor nodes in the first group and the node is less than or equal to R/4, and the communication distance between the neighbor nodes in the second group and the node The communication distance of is greater than R/4 and less than or equal to R/2, and the communication distance between the neighbor nodes in the third group and this node is greater than R/2. The rest of the grouping methods will not be given as examples, and are similar to this.

For example, each node in the network can obtain the Received Signal Strength Indication (RSSI, Received Signal Strength Indication) information between itself and its neighbor nodes through a periodic listening mechanism (for example, using Hello packets), and then obtain the information of the node and its neighbors. The communication distance between nodes can then group multiple neighbor nodes.

It is worth noting that the above method of grouping by communication distance is only a specific embodiment of the present invention, but the present invention is not limited thereto. For example, grouping can also be performed according to other information (such as communication quality), or neighbor nodes can be divided into multiple For group 2 (such as group 3, group 4, etc.), the specific implementation scenario can be determined according to the actual situation.

Fig. 3 is a schematic diagram after grouping neighbor nodes of a node according to an embodiment of the present invention. As shown in Figure 3, node ① is the node, and node ②③④⑤⑥ is its neighbor node. The area (area A in the figure) whose distance from node ① is less than or equal to R/2 (R is the communication range of the node) can be called the primary zone PZ (Primary Zone); within the communication range of node ①, and the distance from node ① The area greater than R/2 (area B in the figure) is called the secondary area SZ (Secondary Zone). Thus, the neighbor nodes can be grouped (for example, the neighbor nodes in the PZ area correspond to the first group, and the neighbor nodes in the SZ area correspond to the second group).

In this embodiment, after the multiple neighbor nodes of a node are divided into different groups, different backoff times may be set for the neighbor nodes of different groups. Thus, the backoff time of neighboring nodes in different groups may not end at the same time, and there may be only one root node determined according to the countdown of the backoff time.

As shown in FIG. 2 , the fault diagnosis device 200 may further include: a time setting unit 205 , which sets different backoff times for different groups of neighboring nodes. Wherein, for multiple neighbor nodes in each group, there may be multiple corresponding backoff times; for example, the backoff times of each neighbor node are different. Therefore, the backoff time of each group can form a range of time.

Also, the time ranges formed by the backoff times of different groups do not overlap with each other. In the following, two groups are taken as an example to illustrate the setting of the backoff time. In this embodiment, a backoff time BO (Backoff) may be set for each neighbor node according to the following rules.

For example, the time setting unit 205 may use the following formula to set the backoff time:

t ₀ ≤t ₁ ≤BO ₁ ≤t ₂ <t ₃ ≤BO ₂ ≤t ₄

Among them, BO ₁ is the backoff time set for the first group of neighbor nodes (such as ④⑤ in Figure 3), and BO ₂ is the backoff time set for the second group of neighbor nodes (such as ②③⑥ in Figure 3); among them, t ₁ , t ₂ , t ₃ , and t ₄ are predetermined times, and t ₀ is the moment when the diagnostic node detects a suspected node failure.

In specific implementation, the following rules can be used to achieve:

BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN)

BO ₂ =t ₃ +(t ₄ -t ₃ )·F(Hop,NN)

F(Hop, NN) is a function whose value is in [0, 1]. F(Hop, NN) is proportional to the hop number Hop of the neighbor node, and inversely proportional to the number of neighbors of the neighbor node.

In the specific implementation, when t ₀ =t ₁ , it means that the countdown of the back-off time starts as soon as the node detects a fault; when t ₀ <t ₁ , it means that the node delays for a period of time after detecting the fault and then starts the countdown of the back-off time countdown. When t ₁ =t ₂ , the node can use the backoff time of the MAC layer CSMA/CA mechanism as its own backoff time; the backoff mechanism in the MAC layer is to ensure that channel conflicts are avoided, and the specific content can refer to the existing technology. The case of t ₃ and t ₄ can be the same as that of t ₁ and t ₂ .

In specific implementation, if there is a gateway node among the neighbor nodes of the suspected node, the gateway can be assigned a backoff time between t ₀ and t ₁ , so that the gateway first ends the countdown of the backoff time and becomes the root node to start the establishment diagnostic tree.

In one embodiment, F(HopNN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

In another embodiment, F(HopNN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order

Fig. 4 is a schematic diagram of the relationship between t ₁ , t ₂ , t ₃ , t ₄ and BO ₁ , BO ₂ in an embodiment of the present invention. As shown in FIG. 4 , BO1 is a certain value between [t ₁ , t ₂ ], and BO2 is a certain value between [t ₃ , t ₄ ]. If there is at least one diagnostic node within the range of R/2 from the suspected node, the period [t ₂ , t ₃ ] guarantees that only one diagnostic node will start the process of establishing the diagnostic tree.

In a specific implementation, the time interval between _t2 and _t3 is a parameter. The interval between _t2 and _t3 can be set as "the time of data packet transmission for 3 hops"; the interval between _t2 and _t3 can also be set as "the time of data packet transmission for 9 hops".

For example, for the scenario shown in Figure 3, the time setting unit 205 in the neighbor node ④⑤ can use BO ₁ =t ₁ +(t ₂ −t ₁ )·F(Hop,NN) to set the backoff time T4, T5; the time setting unit 205 in the neighbor node ②③⑥ can adopt BO ₂ =t ₃ +(t ₄ −t ₃ )·F(Hop,NN) to set the back-off time T2, T3, T6 for node ①. The time setting unit 205 in node ① can also set the backoff time for itself for its neighbor nodes.

It should be noted that the above only schematically illustrates the setting of the backoff time in the present invention, but the present invention is not limited thereto, for example, appropriate deformations may be adopted according to actual conditions, and other formulas may be used.

Fig. 5 is another schematic diagram of the structure of the fault diagnosis device according to the embodiment of the present invention. As shown in FIG. 5 , the fault diagnosis device 500 includes: a time start unit 101 , a root node determination unit 102 , a diagnosis control unit 103 , a grouping unit 204 and a time setting unit 205 , as described above.

As shown in Figure 5, the fault diagnosis device can also include: a node selection unit 505, when there is no neighbor node in the first group, select a neighbor node from the second group as the neighbor node of the first group; and, the time setting unit 205 is also used to set the backoff time corresponding to the first group for the selected neighbor node.

Specifically, the node selection unit 505 may select a neighbor node from the neighbor nodes whose distances are all greater than R/2 as the first group of neighbor nodes when the distances between all neighbor nodes and the diagnostic node are greater than R/2.

As shown in FIG. 5 , the fault diagnosis device may further include: a time sending unit 506 . The time sending unit 506 sends the backoff time set by the time setting unit 205 to the selected neighbor node, so that the neighbor node stores the backoff time.

Wherein, the node selection unit 505 may select the neighbor node closest to the diagnostic node; or, when there are multiple neighbor nodes with the same distance, the node selection unit 505 selects the neighbor node with the smallest hop count; or, when there are multiple When there are several neighbor nodes with the same distance and the same number of hops, the node selection unit 505 randomly selects a neighbor node from them.

Fig. 6 is another schematic diagram after grouping the neighbor nodes of a node according to the embodiment of the present invention. As shown in Figure 6, node ① is the node, and node ②③⑥ is its neighbor node. The area (area A in the figure) whose distance from node ① is less than or equal to R/2 (R is the communication range of the node) can be called the main area PZ; within the communication range of node ①, and the distance from node ① is greater than R/2 The area (area B in the figure) is called the secondary area SZ.

As shown in Figure 6, there are no neighbor nodes in area A, but there are neighbor nodes ②③⑥ in area B. In the specific implementation, for example, in the case that there is no node in PZ (area A) in Figure 6, that is, when the node ① finds that the distance between the neighbor nodes and itself is greater than R/2, the node ① chooses a node that is closest to itself (e.g. node ②). If there are multiple neighbor nodes with the same distance, select the neighbor node with the smallest hop count; if there are multiple neighbor nodes with the same hop count, choose randomly from them.

After selecting the neighbor node (such as node ②), node ① can set a BACKOFF time within [t1, t2] for the neighbor node ②, and send this time to the neighbor node.

In this embodiment, the time start unit 101 can be specifically configured to: when the diagnosis node does not receive multiple interception packets (Hello packets) from the suspect node continuously, start the countdown of the backoff time for the suspect node, and can set The suspected node is stored locally as a local suspected node LSN (Local Suspect Node).

In this embodiment, the diagnosis control unit 103 can also be used to: after the root node determination unit 102 determines the root node, control the root node to broadcast a detection packet DP (Detection Packet); so that other diagnostic nodes do not end the countdown of the backoff time and When the detection packet is received, the countdown of the backoff time is no longer performed. Wherein, other diagnostic nodes refer to one or more diagnostic nodes other than the diagnostic node determined as the root node.

In actual implementation, for example, when node A discovers that its neighbor node B has not received K consecutive Hello packets, node A thinks that node B needs to be diagnosed, and stores node B locally, which is recorded as LSN (Local SN) . If the back-off time BO of node A ends, a diagnostic tree can be established and a detection packet DP is broadcast; if node A receives the detection packet DP sent by other nodes before the BO countdown is over, the BO countdown is no longer performed, and Continue to broadcast the detection packet DP (it should be pointed out that if the node that has joined the diagnosis tree receives the DP packet again, it will not broadcast again).

During specific implementation, the detection packet DP may include the source address, identification information of the suspected node, and identification information of the root node. In addition, the frame type (Frame Type) and reserved bits (Reserved) can also be included.

FIG. 7 is a schematic structural diagram of a detection packet according to an embodiment of the present invention. As shown in Figure 7, it can include: the source address of the DP packet (which can be represented by GS); the frame type (FT, Frame Type), indicating that the packet is a detection packet; the suspected node identifier (which can be represented by SN ID); the root node Identification (can be represented by RN ID); and reserved bit (can be represented by Reserved).

In this embodiment, after a node receives a DP, if it finds that the SN ID of the DP is the same as the locally stored LSN, it can change the GS of the DP to its own address and continue broadcasting the DP; if it finds that the SN ID If it is the same as a neighbor node in the local neighbor table, continue to broadcast the DP; if it is found that the SN ID is not in the local neighbor table, the DP will not be broadcast (indicating that the node is not a neighbor node of the SN).

It can be seen from the above embodiments that when a suspected node needs to be diagnosed, start the back-off time of the diagnostic node for the suspected node, determine the root node according to the countdown to the back-off time, and start the establishment of the diagnostic tree by the root node, and receive the nodes in the diagnostic tree The diagnostic information sent, and the diagnostic results are reported to the gateway. In this way, a unified diagnosis result can be obtained at the gateway, while reducing the communication overhead of the system.

Example 2

An embodiment of the present invention provides a fault diagnosis method, which corresponds to the fault diagnosis device in Embodiment 1. Fig. 8 is a schematic flow chart of a fault diagnosis method according to an embodiment of the present invention. As shown in Fig. 8, the fault diagnosis method includes:

Step 801, when the suspected node needs to be diagnosed, start the backoff time of the suspected node for the diagnosed node;

Step 802, determine the root node according to the countdown of the backoff time; the root node is the diagnostic node whose backoff time ends first among the multiple diagnostic nodes of the suspected node;

Step 803, control the root node to start establishing a diagnosis tree, receive diagnosis information sent by nodes in the diagnosis tree, and report the diagnosis result to the gateway.

In this embodiment, the backoff time may be predetermined. For each diagnostic node, multiple neighbor nodes of the diagnostic node can be divided into different groups, and different backoff times can be set for different groups of neighbor nodes.

Specifically, dividing the multiple neighbor nodes of the diagnosis node into different groups may specifically include: dividing the multiple neighbor nodes into multiple different groups according to communication distances. For example, it can be divided into the first group and the second group; the communication distance between the neighbor nodes in the first group and the diagnosis node is less than or equal to R/2, and the communication distance between the neighbor nodes in the second group and the diagnosis node is greater than R /2; Among them, R is the communication range of the diagnosis node.

In an implementation manner, the implementation scenario may be as shown in FIG. 3 . Neighbor nodes exist in both the first group (for example, area A in Figure 3 ) and the second group (for example, area B in Figure 3 ). Different backoff times can be set for different groups of neighbor nodes.

In another implementation manner, the implementation scenario may be as shown in FIG. 6 . When the distances between all neighbor nodes and the diagnostic node are greater than R/2, a neighbor node may be selected as the first group of neighbor nodes. Wherein, selecting a neighbor node as the neighbor node of the first group may specifically include: selecting the neighbor node closest to the diagnostic node; or, when there are multiple neighbor nodes with the same distance, selecting the neighbor node with the smallest hop count ; Or, when there are multiple neighbor nodes with the same distance and the same number of hops, randomly select a neighbor node from them.

In this embodiment, the fault diagnosis method may further include: sending the set backoff time to the selected neighbor node, so that the neighbor node stores the backoff time.

In this embodiment, when the suspected node needs to be diagnosed in step 801, starting the backoff time of the diagnosing node for the suspected node may specifically include: when the diagnosing node does not continuously receive multiple Hello packets from the suspected node, starting backoff The time starts counting down, and the suspect node is stored locally as a local suspect node.

In this embodiment, after the root node is determined in step 802, the fault diagnosis method may further include: controlling the root node to broadcast a detection packet; so that other diagnosis nodes do not perform any further operations when the backoff time countdown has not ended and the detection packet is received. Countdown for backoff time. Wherein, the detection packet may include source address, identification information of the suspected node, and identification information of the root node. For the structure of the detection packet, please refer to the content in Fig. 7 .

In this embodiment, the fault diagnosis method may also include: after a certain diagnosis node receives the detection packet, if it is found that the identification information of the suspected node in the detection packet is the same as the local suspected node stored locally, then the detection packet Change the source address of the diagnostic node to its own address, and then continue to broadcast the detection packet; if the identification information of the suspected node in the detection packet is found to be the same as a neighbor node in the local neighbor table, continue to broadcast the detection packet; if the detection packet is found If the identification information of the suspected node is not in the local neighbor table, the detection packet will not be broadcast.

Fig. 9 is another schematic flowchart of a fault diagnosis method according to an embodiment of the present invention. As shown in Fig. 9, the fault diagnosis method includes:

Step 901, the diagnosis node counts the Hello packets sent by the suspect node.

Step 902, judging whether K Hello packets sent by the suspected node have not been continuously received; if not, then step 903 is executed.

In step 903, the diagnosis node considers that the suspected node needs to be diagnosed, and starts counting down the backoff time.

Step 904, judging whether the countdown of the backoff time is over; if the countdown is over, go to step 905, otherwise go to step 907.

Specifically, the backoff time BO of the diagnostic node for the suspect node can be judged; if BO is greater than 0, the backoff time has not ended, and step 907 is performed; if BO is less than or equal to 0, the backoff time is over, and step 905 is performed.

Step 905, determine that the diagnostic node is the root node, start building a diagnostic tree and broadcast a detection packet DP.

Step 906, collecting diagnostic information and reporting the diagnostic result to the gateway.

Step 907, judging whether the detection packet DP sent by other nodes is received; if the detection packet DP is received, execute step 908, otherwise execute step 904.

Step 908, stop the countdown of the backoff time, join the diagnosis tree established by other nodes and continue to broadcast the detection packet DP.

In addition, if the node receiving the detection packet DP finds that the identification information of the suspected node of the detection packet DP is not in the local neighbor table, it indicates that the node is not a neighbor node of the suspected node, so the detection packet DP is not broadcast. Moreover, after receiving the detection packet again, the nodes that have been added to the diagnosis tree may not broadcast the detection packet any more.

The scenario shown in FIG. 3 is taken as an example below for description. In the scenario shown in Figure 3, it is assumed that for node ①, backoff times have been set for neighbor nodes ②③④⑤⑥, which are T2, T3, T4, T5, and T6 respectively. For the specific setting method, please refer to Embodiment 1 or Embodiment 3.

When node ① needs to be diagnosed as a suspected node, node ②③④⑤⑥, as a diagnostic node, starts the backoff time countdown. For one of the diagnostic nodes (such as node ⑤), if T5=0 (that is, the earliest end backoff time), it can be determined that the node ⑤ is the root node, and the node ⑤ starts to build a diagnostic tree and sends a detection packet DP.

For other diagnostic nodes (such as node ②③④⑥), if the detection packet DP sent by the node ⑤ is received, the countdown of the backoff time will be stopped, join the diagnostic tree and continue to broadcast the detection packet DP. Thus, a diagnostic tree can be established by node ⑤, and diagnostic information can be collected and sent to the gateway.

It can be seen from the above embodiments that when a suspected node needs to be diagnosed, start the back-off time of the diagnostic node for the suspected node, determine the root node according to the countdown to the back-off time, and start the establishment of the diagnostic tree by the root node, and receive the nodes in the diagnostic tree The diagnostic information sent, and the diagnostic results are reported to the gateway. In this way, a unified diagnosis result can be obtained at the gateway, while reducing the communication overhead of the system.

Example 3

The embodiment of the present invention provides a backoff time setting method, which can be used as a part of embodiment 2 or a pre-preparation process, and has the same content as the setting part of the backoff time in embodiment 1, which will not be repeated here.

FIG. 10 is a schematic flowchart of a method for setting backoff time according to an embodiment of the present invention. As shown in FIG. 10 , the setting method includes:

Step 1001, dividing multiple neighbor nodes of the node into different groups;

Step 1002, setting different backoff times for different groups of neighbor nodes.

In this embodiment, for any node, multiple neighbor nodes of the node may be divided into different groups, and then a backoff time is set. Thus, the backoff time of neighboring nodes in different groups may not end at the same time, and there may be only one root node determined according to the countdown of the backoff time.

During specific implementation, in step 1001, dividing multiple neighboring nodes of a node into different groups may specifically include: dividing multiple neighboring nodes into multiple different groups according to communication distances. For example, it can be divided into the first group and the second group, the communication distance between the neighbor nodes in the first group and the node is less than or equal to R/2, and the communication distance between the neighbor nodes in the second group and the node is greater than R/2 ; Among them, R is the communication range of the node.

It is worth noting that the above method of grouping by communication distance is only a specific embodiment of the present invention, but the present invention is not limited thereto. For example, grouping can also be performed according to other information (such as communication quality), or neighbor nodes can be divided into multiple For group 2 (such as group 3, group 4, etc.), the specific implementation scenario can be determined according to the actual situation.

During specific implementation, the following rules can be used to set the backoff time in step 1002:

t ₀ ≤t ₁ ≤BO ₁ ≤t ₂ <t ₃ ≤BO ₂ ≤t ₄

Among them, BO ₁ is the backoff time set for the first group of neighbor nodes, BO ₂ is the backoff time set for the second group of neighbor nodes; t ₁ , t ₂ , t ₃ , t ₄ are predetermined times.

In specific implementation, the following rules can be used to achieve:

BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN)

BO ₂ =t ₃ +(t ₄ -t ₃ )·F(Hop,NN)

F(Hop, NN) is a function whose value is in [0, 1]. F(Hop, NN) is proportional to the hop number Hop of the node and inversely proportional to the number of neighbors of the node.

In one embodiment, F(Hop, NN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

In another embodiment, F(HopNN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order

It is worth noting that the above formula is only a schematic illustration of the setting of the backoff time in the present invention, but the present invention is not limited thereto, and appropriate deformations may be adopted according to actual conditions, and other formulas may be used.

In this embodiment, the backoff time may be set on the node, and the setting method may further include: sending the set backoff time to each neighbor node, so that each neighbor node stores the corresponding backoff time respectively.

In addition, the setting of the backoff time can also be performed on each neighbor node, and each neighbor node sets the backoff time for the node respectively. In the following, each neighbor node sets the backoff time for the node as an example for illustration.

FIG. 11 is an example diagram of a method for setting backoff time according to an embodiment of the present invention. Taking the scene shown in FIG. 3 as an example, it shows the situation that there are neighbor nodes in both the first group and the second group. As shown in Figure 11, the setting method includes:

Step 1101, start the Hello process.

Step 1102, calculate the distance between nodes.

Specifically, the distance between nodes can be calculated using the RSSI information included in the Hello packet, but the present invention is not limited thereto.

Step 1103, for a neighbor node of the node, judge whether the distance between the node and the neighbor node is less than R/2; if yes, execute step 1104; if not, execute step 1105.

Step 1104, the neighbor node uses the formula BO ₁ =t ₁ +(t ₂ −t ₁ )·F(Hop,NN) to set the backoff time.

Step 1105, the neighbor node uses the formula BO ₂ =t ₃ +(t ₄ -t ₃ )·F(Hop,NN) to set the backoff time.

For example, in the scenario shown in FIG. 3 , neighbor nodes ④⑤ can use BO ₁ =t ₁ +(t ₂ −t ₁ )·F(Hop,NN) to set the backoff time for node ①. Among them, F(Hop,NN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

Alternatively, F(Hop,NN) can use the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order Hop is the hop number of node ④ or ⑤, and NN is the number of neighbors of node ④ or ⑤.

The neighbor node ②③⑥ can use BO ₂ =t ₃ +(t ₄ −t ₃ )·F(Hop,NN) to set the backoff time for node ①. Among them, F(Hop,NN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

Alternatively, F(Hop,NN) can use the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order Hop is the hop number of node ②, ③ or ⑥, and NN is the number of neighbors of node ②, ③ or ⑥.

FIG. 12 is another example diagram of the backoff time setting method according to the embodiment of the present invention. Taking the scenarios shown in FIG. 3 and FIG. 6 as examples, it shows that there may be no neighbor nodes in the first group. As shown in Figure 12, the setting method includes:

Step 1201, start the Hello process.

Step 1202, calculate the distance between nodes, and divide them into a first area and a second area according to the distance.

Step 1203, judging whether there is a neighbor node in the first area; if there is no neighbor node, go to step 1205; if there is a neighbor node, go to step 1204.

Step 1204, the neighbor nodes of the node set the backoff time respectively according to the groups.

Specifically, the backoff time may be set according to steps 1103 to 1105 in FIG. 11 .

Step 1205, the node selects a node from the neighbor nodes, and uses the formula in the first area to set the backoff time for the neighbor node, that is, BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN) .

Specifically, you can select the neighbor node closest to the node; or, when there are multiple neighbor nodes with the same distance, select the neighbor node with the smallest hop number; or, when there are multiple neighbor nodes with the same distance and the same number of hops When a neighbor node is selected, a neighbor node is randomly selected from it.

Step 1206, the node sends the backoff time to the selected neighbor node.

Step 1207, after receiving the backoff time, the selected neighbor node stores the backoff time locally.

For example, in the scenario shown in Figure 6, node ① can select a neighbor node (such as node ②), and then node ① can adopt BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN) to set the backoff time of node ②.

Among them, F(Hop,NN) can adopt the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

Alternatively, F(Hop,NN) can use the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order Hop is the hop number of node ②, and NN is the number of neighbors of node ②.

Then, node ① can send the backoff time to node ②, and node ② replaces the previously calculated backoff time with the received backoff time, and stores the updated backoff time locally.

It can be known from the above embodiments that by dividing multiple neighbor nodes of a node into different groups, and setting different backoff times for the neighbor nodes of different groups. It is possible to prevent the backoff time of neighboring nodes in different groups from ending at the same time, and ensure that there is only one root node counting down according to the backoff time.

Example 4

An embodiment of the present invention further provides a network node, where the network node includes the fault diagnosis device as described in Embodiment 1. Fig. 13 is a schematic diagram of a network node in an embodiment of the present invention. As shown in Fig. 13, there may be multiple network nodes 1301, 1302, 1303, etc. in the network, and one or more network nodes (such as network node 1301) may have time A startup unit 101 , a root node determination unit 102 and a diagnosis control unit 103 .

In addition, as a modification, the fault diagnosis device of the present invention may also be centralized. Fig. 14 is another schematic diagram of a network node according to an embodiment of the present invention. As shown in Fig. 14, there may be multiple network nodes 1301, 1302, 1303, and so on. In addition, there may also be a fault diagnosis device 1304 in the network. The fault diagnosis device 1304 has a time start unit 101, a root node determination unit 102, and a diagnosis control unit 103, and controls the network nodes 1301, 1302, 1303, etc. to realize the network node fault diagnosis.

The above devices and methods of the present invention can be implemented by hardware, or by combining hardware and software. The present invention relates to such a computer-readable program that, when the program is executed by a logic component, enables the logic component to realize the above-mentioned device or constituent component, or enables the logic component to realize the above-mentioned various methods or steps. The present invention also relates to a storage medium for storing the above program, such as hard disk, magnetic disk, optical disk, DVD, flash memory and the like.

The present invention has been described above in conjunction with specific embodiments, but those skilled in the art should be clear that these descriptions are all exemplary and not limiting the protection scope of the present invention. Those skilled in the art can make various variations and modifications to the present invention according to the spirit and principle of the present invention, and these variations and modifications are also within the scope of the present invention.

Regarding the implementation manner comprising the above embodiments, the following additional notes are also disclosed:

(Additional Note 1) A fault diagnosis device, which includes:

A time starting unit, when the suspected node needs to be diagnosed, starts the backoff time of the diagnostic node for the suspected node;

The root node determination unit determines the root node according to the countdown of the back-off time; the root node is the diagnostic node whose back-off time ends first among the multiple diagnostic nodes of the suspected node;

The diagnosis control unit controls the root node to start establishing the diagnosis tree, receives the diagnosis information sent by the nodes in the diagnosis tree, and reports the diagnosis result to the gateway.

(Supplement 2) The fault diagnosis device according to Supplement 1, wherein the fault diagnosis device further includes:

A grouping unit, which divides the multiple neighbor nodes of the suspected node into different groups.

(Supplementary Note 3) The fault diagnosis device according to Supplementary Note 2, wherein the grouping unit is specifically configured to: divide the plurality of neighboring nodes into a first group and a second group according to the communication distance;

The communication distance between the neighbor nodes in the first group and the suspect node is less than or equal to R/2, and the communication distance between the neighbor nodes in the second group and the suspect node is greater than R/2; wherein, the R is the communication range of the suspected node.

(Supplement 4) The fault diagnosis device according to any one of Supplements 1 to 3, wherein the fault diagnosis device further includes:

The time setting unit is configured to set the back-off time according to the different groups into which the multiple neighbor nodes of the suspected node are divided; wherein, the time ranges formed by the back-off times of different groups do not overlap with each other.

(Supplementary Note 5) The fault diagnosis device according to Supplementary Note 4, wherein the time setting unit adopts the following rule to set the backoff time:

t ₀ ≤t ₁ ≤BO ₁ ≤t ₂ <t ₃ ≤BO ₂ ≤t ₄

Wherein, BO ₁ is the backoff time set for the first group of neighbor nodes, BO ₂ is the backoff time set for the second group of neighbor nodes; t ₁ , t ₂ , t ₃ , t ₄ are predetermined Time, t ₀ is the moment when the diagnostic node detects the suspected node failure.

(Supplementary Note 6) The fault diagnosis device according to Supplementary Note 5, wherein,

BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN)

BO ₂ =t ₃ +(t ₄ -t ₃ )·F(Hop,NN)

F(Hop, NN) is a function whose value is in [0, 1]. The F(Hop, NN) is proportional to the hop number Hop of the node and inversely proportional to the number of neighbors of the node.

(Supplementary Note 7) The fault diagnosis device according to Supplementary Note 6, wherein the F(Hop, NN) adopts the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

(Supplementary Note 8) The fault diagnosis device according to Supplementary Note 6, wherein the F(Hop, NN) adopts the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order

(Supplementary note 9) The fault diagnosis device according to supplementary note 3, wherein the fault diagnosis device further includes:

The node selection unit selects a neighbor node from the second group as the neighbor node of the first group when the neighbor node of the first group is empty; and sets the corresponding neighbor node for the selected neighbor node. The backoff time of the first group.

(Supplementary Note 10) The fault diagnosis device according to Supplementary Note 9, wherein the node selection unit selects a neighbor node closest to the suspected node;

Or, when there are multiple neighbor nodes with the same distance, the node selection unit selects the neighbor node with the smallest hop count;

Or, when there are multiple neighbor nodes with the same distance and multiple hops, the node selection unit randomly selects a neighbor node from among them.

(Supplement 11) The fault diagnosis device according to Supplement 9 or 10, wherein the fault diagnosis device further includes:

The time sending unit is configured to send the set backoff time to the neighbor node, so that the neighbor node stores and uses the backoff time.

(Supplementary Note 12) The fault diagnosis device according to Supplementary Note 1, wherein the time start unit is specifically configured to start the backoff when the diagnosis node does not receive multiple Hello packets from the suspect node continuously The time starts counting down, and the suspect node is stored locally as a local suspect node.

(Supplementary Note 13) The fault diagnosis device according to Supplementary Note 12, wherein the diagnostic control unit is further configured to control the root node to broadcast a detection packet; so that other diagnostic nodes receive the When detecting packets, the countdown of the backoff time is no longer performed.

(Supplementary Note 14) The fault diagnosis device according to Supplementary Note 13, wherein the detection packet includes a source address, identification information of the suspected node, and identification information of the root node.

(Additional Note 15) A fault diagnosis method, the fault diagnosis method comprising:

When the suspected node needs to be diagnosed, start the backoff time of the diagnosed node for the suspected node;

Determine the root node according to the countdown to the backoff time; the root node is the diagnostic node whose backoff time ends first among the plurality of diagnostic nodes of the suspect node;

Controlling the root node to start establishing a diagnosis tree, receiving diagnosis information sent by nodes in the diagnosis tree, and reporting a diagnosis result to the gateway.

(Supplement 16) The fault diagnosis method according to Supplement 15, wherein the fault diagnosis method further includes:

Divide multiple neighbor nodes of the suspected node into different groups, and set different backoff times for different groups of neighbor nodes.

(Supplementary Note 17) The fault diagnosis method according to Supplementary Note 16, wherein dividing the plurality of neighbor nodes of the diagnosis node into different groups specifically includes:

Divide the multiple neighbor nodes into a first group and a second group according to the communication distance; the communication distance between the neighbor nodes in the first group and the suspected node is less than or equal to R/2, and in the second group The communication distance between the neighbor node and the suspected node is greater than R/2; wherein, the R is the communication range of the suspected node.

(Supplement 18) The fault diagnosis method according to Supplement 17, wherein the fault diagnosis method further includes:

When all the distances between the neighbor nodes and the suspected node are greater than R/2, select a neighbor node as the neighbor node of the first group.

(Supplementary Note 19) The fault diagnosis method according to Supplementary Note 18, wherein selecting a neighbor node as the neighbor node of the first group specifically includes:

Select the nearest neighbor node from the suspected node;

Or, when there are multiple neighbor nodes with the same distance, select the neighbor node with the smallest hop count;

Or, when there are multiple neighbor nodes with the same distance and multiple hops, a neighbor node is randomly selected from them.

(Supplement 20) The fault diagnosis method according to Supplement 18 or 19, wherein the fault diagnosis method further includes:

Sending the set backoff time to the neighbor node, so that the neighbor node stores and uses the backoff time.

(Supplementary Note 21) The fault diagnosis method according to Supplementary Note 15, wherein when the suspected node needs to be diagnosed, starting the backoff time of the diagnostic node for the suspected node specifically includes:

When the diagnostic node does not continuously receive multiple Hello packets from the suspect node, start the countdown of the backoff time, and store the suspect node locally as a local suspect node.

(Supplement 22) The fault diagnosis method according to Supplement 21, wherein the fault diagnosis method further includes:

Controlling the root node to broadcast a detection packet; so that when the countdown of the backoff time is not over and the other diagnostic nodes receive the detection packet, the countdown of the backoff time is no longer performed.

(Supplementary Note 23) The fault diagnosis method according to Supplementary Note 22, wherein the detection packet includes a source address, identification information of the suspected node, and identification information of the root node.

(Supplementary Note 24) The fault diagnosis method according to Supplementary Note 22, wherein the fault diagnosis method further includes:

After a certain diagnostic node receives the detection packet, if it is found that the identification information of the suspected node in the detection packet is the same as the local suspected node stored locally, then the source address of the detection packet is changed to the diagnostic node itself address, and then continue to broadcast the detection packet;

If it is found that the identification information of the suspected node of the detection packet is the same as a certain neighbor node in the local neighbor table, then continue to broadcast the detection packet;

If it is found that the identification information of the suspected node of the detection packet is not in the local neighbor table, the detection packet is not broadcast.

(Supplementary note 25) A method for setting back-off time, the setting method comprising:

Divide multiple neighbor nodes of a node into different groups;

Different back-off times are set for different groups of neighbor nodes, and the time ranges formed by the back-off times of different groups do not overlap each other.

(Supplementary Note 26) The setting method according to Supplementary Note 25, wherein dividing the multiple neighboring nodes of the node into different groups specifically includes: dividing the multiple neighboring nodes into multiple different groups according to the communication distance.

(Supplementary Note 27) The setting method according to Supplementary Note 26, wherein the multiple neighbor nodes are divided into a first group and a second group according to the communication distance, and the neighbor nodes in the first group and the node The communication distance is less than or equal to R/2, and the communication distance between the neighbor nodes in the second group and the node is greater than R/2; wherein, the R is the communication range of the node.

(Supplementary Note 28) The setting method according to any one of Supplementary Notes 25 to 27, wherein the following rule is used to set the backoff time: t ₀ ≤t ₁ ≤BO ₁ ≤t ₂ <t ₃ ≤BO ₂ ≤t ₄ ;

Among them, BO ₁ is the backoff time set for the first group of neighbor nodes, BO ₂ is the backoff time set for the second group of neighbor nodes; t ₁ , t ₂ , t ₃ , t ₄ are predetermined times.

(Supplementary Note 29) The setting method according to Supplementary Note 28, wherein,

BO ₁ =t ₁ +(t ₂ -t ₁ )·F(Hop,NN)

BO ₂ =t ₃ +(t ₄ -t ₃ )·F(Hop,NN)

F(Hop, NN) is a function whose value is in [0, 1]. The F(Hop, NN) is proportional to the hop number Hop of the node and inversely proportional to the number of neighbors of the node.

(Supplementary Note 30) The setting method according to Supplementary Note 29, wherein the F(Hop, NN) adopts the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; arctg</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

in, ε is a random parameter with a value in [0,0.5].

(Supplementary Note 31) The setting method according to Supplementary Note 29, wherein the F(Hop, NN) adopts the following formula:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; Hop</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; NN</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; sin</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; Hop</span>}}{\mathrm{<span\; class="notranslate">\; NN</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&epsiv;</span>}$

or, $f(\mathrm{Hop},\mathrm{NN})=\mathrm{\&alpha;}\&Center\; Dot;(\cos \left(\frac{\mathrm{Hop}}{\mathrm{NN}}\right)+1)+\mathrm{\&epsiv;}$

in, ε is a random parameter with a value in [0,0.5]; and if order

(Supplementary Note 32) The setting method according to Supplementary Note 27, wherein the said setting method further includes:

When all the distances between the neighbor nodes and the node are greater than R/2, select a neighbor node as the neighbor node of the first group.

(Supplementary Note 33) A network node, including the fault diagnosis device according to any one of Supplementary Notes 1 to 14.

(Supplementary Note 34) A computer-readable program, wherein, when the program is executed in a network node, the program causes a computer to execute the fault described in any one of Supplementary Notes 15 to 24 in the network node. Diagnosis method, or the setting method of backoff time as described in any one of Supplementary Notes 25 to 31.

(Supplementary Note 35) A storage medium storing a computer-readable program, wherein the computer-readable program causes a computer to execute the fault diagnosis method described in any one of Supplementary Notes 15 to 24 in a network node, or as described in The method for setting the backoff time described in any one of Supplementary Notes 25 to 31.

Claims (15)

1. A failure diagnosis device, comprising:

the time starting unit is used for starting the back-off time of the diagnosis node aiming at the doubtful node when the doubtful node needs to be diagnosed; wherein the back-off time is set by grouping a plurality of neighbor nodes of the suspect node into different groups;

a root node determination unit configured to determine a root node from the countdown of the back-off time; the root node is a diagnosis node with the first end of the back-off time in a plurality of diagnosis nodes of the suspect node;

and the diagnosis control unit controls the root node to start building a diagnosis tree, receives diagnosis information sent by the nodes in the diagnosis tree and reports a diagnosis result to the gateway.

2. The fault diagnosis device according to claim 1, wherein the fault diagnosis device further includes:

and the grouping unit is used for dividing the plurality of neighbor nodes of the suspected node into a plurality of different groups according to the communication distance.

3. The failure diagnosis apparatus according to claim 2, wherein the grouping unit groups a plurality of neighbor nodes of the suspect node into a first group and a second group according to communication distances;

the communication distance between the neighbor nodes in the first group and the suspected node is less than or equal to R/2, and the communication distance between the neighbor nodes in the second group and the suspected node is greater than R/2; wherein the R is the communication range of the suspected node.

4. The fault diagnosis device according to any one of claims 1 to 3, wherein the fault diagnosis device further includes:

and the time setting unit is used for setting the back-off time according to different groups, wherein the time ranges formed by the back-off times of the different groups are not overlapped with each other.

5. The fault diagnosis device according to claim 4, wherein the time setting unit sets the back-off time using the following rule:

t₀≤t₁≤BO₁≤t₂<t₃≤BO₂≤t₄

wherein, BO₁Is a back-off time, BO, set for the neighbor nodes of the first group₂Is a back-off time set for a neighbor node of the second group; t is t₁、t₂、t₃、t₄Is a predetermined time, t₀The moment when the suspected node fault is detected for the diagnostic node.

6. The failure diagnostic device according to claim 5,

BO₁=t₁+(t₂-t₁)·F(Hop,NN)

BO₂=t₃+(t₄-t₃)·F(Hop,NN)

f (Hop, NN) is a function with a value of [0,1], and is in direct proportion to Hop count Hop of a node and in inverse proportion to the number NN of neighbors of the node.

7. The fault diagnosis device according to claim 3, wherein the fault diagnosis device further includes:

a node selecting unit, selecting a neighbor node from the second group as a neighbor node of the first group when the neighbor node of the first group is empty; and setting back-off time corresponding to the first group for the selected neighbor node.

8. The fault diagnosis device according to claim 7, wherein the fault diagnosis device further includes:

and the time sending unit is used for sending the back-off time to the selected neighbor node so that the neighbor node stores and uses the back-off time.

9. The failure diagnosis apparatus according to claim 1, wherein the diagnosis control unit is further configured to control the root node to broadcast a detection packet; and when the back-off time counting down is not finished and the detection packet is received, other diagnosis nodes do not count down the back-off time any more.

10. A fault diagnosis method, comprising:

when a suspected node needs to be diagnosed, starting the back-off time of the suspected node by a diagnosis node; wherein the back-off time is set by grouping a plurality of neighbor nodes of the suspect node into different groups;

determining a root node according to the back-off time countdown; the root node is a diagnosis node with the first end of the back-off time in a plurality of diagnosis nodes of the suspect node;

and controlling the root node to start building a diagnosis tree, receiving diagnosis information sent by the nodes in the diagnosis tree, and reporting a diagnosis result to a gateway.

11. A method of setting a back-off time, the method comprising:

dividing a plurality of neighbor nodes of a node into different groups;

different back-off times are set for the neighbor nodes of different groups, wherein the time ranges formed by the back-off times of different groups are not overlapped with each other.

12. The provisioning method of claim 11, wherein grouping a plurality of neighbor nodes of a node into different groups includes: a plurality of neighbor nodes of the node are divided into a plurality of different groups according to the communication distance.

13. The provisioning method of claim 12, wherein the plurality of neighbor nodes are grouped into a first group and a second group according to communication distance;

the communication distance between the neighbor node in the first group and the node is less than or equal to R/2, and the communication distance between the neighbor node in the second group and the node is greater than R/2; wherein, the R is the communication range of the node.

14. The setting method according to any one of claims 11 to 13, wherein the back-off time is set using the following rule:

t₀≤t₁≤BO₁≤t₂<t₃≤BO₂≤t₄

wherein, BO₁Is a back-off time, BO, set for the neighbor nodes of the first group₂Is a back-off time set for a neighbor node of the second group; t is t₁、t₂、t₃、t₄Is a predetermined time; t is t₀To diagnose the moment when a node failure is detected by the node.

15. The setting method as recited in claim 14,

BO₁=t₁+(t₂-t₁)·F(Hop,NN)

BO₂=t₃+(t₄-t₃)·F(Hop,NN)

f (Hop, NN) is a function with a value of [0,1], and is in direct proportion to Hop count Hop of a node and in inverse proportion to the number of neighbors of the node.