CN115277374A

CN115277374A - Main/standby switching method and device

Info

Publication number: CN115277374A
Application number: CN202210738495.2A
Authority: CN
Inventors: 刘小龙
Original assignee: New H3C Technologies Co Ltd
Current assignee: New H3C Technologies Co Ltd
Priority date: 2022-06-27
Filing date: 2022-06-27
Publication date: 2022-11-01

Abstract

The application provides a main/standby switching method and device. The method is applied to the vehicle-mounted AP and comprises the following steps: after power-on, broadcasting a first negotiation message carrying the MAC address of the first negotiation message; judging whether the vehicle-mounted AP is a decision AP or not according to the MAC address of the vehicle-mounted AP and the MAC address carried in the received second negotiation message broadcasted by the other vehicle-mounted AP; if so, determining that the AP is a main AP, establishing Socket connection with another vehicle-mounted AP, and informing the other vehicle-mounted AP of being a standby AP; determining the operation role of the user according to a set period; when the operation role is a locomotive AP, if the self is a main AP, informing another vehicle-mounted AP to upgrade to the main AP, and if the self is a standby AP, not doing any operation; when the operation role is the tail AP, if the operation role is the main AP, no operation is performed, and if the operation role is the standby AP, another vehicle-mounted AP is informed to be degraded into the standby AP, and the vehicle-mounted AP is upgraded into the main AP. The method and the device can save network deployment cost.

Description

Main/standby switching method and device

Technical Field

The present application relates to the field of wireless technologies, and in particular, to a method and an apparatus for active/standby switching.

Background

A Mesh network may provide wireless Access, and a multi-hop Mesh link may be established through an Access Point (AP) in the Mesh network. Based on the characteristics of the Mesh network, the Mesh network is widely applied to the scenes such as subways, railways and the like.

Taking a subway scene as an example, a plurality of trackside APs are deployed beside a track of a subway, and a vehicle-mounted AP is deployed at each of two ends of each train. Along the traveling direction of a train, a vehicle-mounted AP (which may be referred to as a tail AP at this time) deployed at the tail of the train is usually used as a main AP, mesh links can be respectively established with a plurality of trackside APs, one of the Mesh links with the best link quality is used as a main Mesh link for related data transmission, and the other Mesh links are used as standby Mesh links.

When the train needs to turn back, the original main AP needs to be switched to the standby AP (which can be called as a train head AP at this moment), and the original standby AP needs to be switched to the main AP. At present, the driver and the passenger usually trigger the vehicle-mounted system to complete the switching operation of the vehicle head AP and the vehicle tail AP in a manual mode, for example, the driver and the passenger trigger the vehicle-mounted system to complete the switching operation of the vehicle head AP and the vehicle tail AP in a mode of inserting a key.

Because the vehicle-mounted systems used by each subway line in each city are different, the main/standby switching mode needs research personnel to develop different vehicle-mounted systems, which results in higher network deployment cost.

Disclosure of Invention

In order to overcome the problems in the related art, the application provides a method and a device for switching between a main standby mode and a standby mode.

According to a first aspect of an embodiment of the present application, a method for switching between a master device and a slave device is provided, where the method is applied to a vehicle-mounted AP, and the method includes:

after power-on, broadcasting a first negotiation message carrying the MAC address of the first negotiation message;

when a second negotiation message broadcasted after another vehicle-mounted AP on the train where the vehicle-mounted AP is positioned is powered on is received, judging whether the vehicle-mounted AP is a decision AP or not according to the MAC address and the MAC address of the another vehicle-mounted AP carried in the second negotiation message;

if so, determining the AP as a main AP, working on a Mesh link established between the AP and the determined main trackside AP, establishing Socket connection with the other vehicle-mounted AP, and informing the other vehicle-mounted AP of being a standby AP;

according to a set period, acquiring locally recorded MAC addresses of all first trackside APs, the signal intensities of which are scanned in the set period by the local recording are not less than a set threshold value, a first time stamp when the local recording MAC addresses of all first trackside APs are scanned in each first trackside AP, MAC addresses of all second trackside APs, the signal intensities of which are scanned by the other vehicle-mounted AP and are sent in the set period by the other vehicle-mounted AP are not less than the set threshold value, and a second time stamp when the local recording MAC addresses of all second trackside APs are received by the local recording MAC addresses of all second trackside APs;

determining the operation role of the self-tracking system according to the obtained MAC addresses and all first time stamps of all the first trackside APs, and the obtained MAC addresses and all second time stamps of all the second trackside APs;

when the determined operation role is the head AP, if the self is the main AP, informing the other vehicle-mounted AP to upgrade to the main AP, degrading the self to the standby AP, disconnecting the currently working Mesh link, and if the self is the standby AP, not doing any operation;

and when the determined running role is the tail AP, if the self is the main AP, no operation is performed, if the self is the standby AP, the other vehicle-mounted AP is informed to be degraded into the standby AP, and the self is upgraded into the main AP to work on a Mesh link established between the self and the currently determined main trackside AP.

According to a second aspect of the embodiments of the present application, there is provided a main/standby switching device, where the device is applied to a vehicle-mounted AP, and the device includes:

the broadcasting module is used for broadcasting a first negotiation message carrying the MAC address of the broadcasting module after the broadcasting module is electrified;

the judging module is used for judging whether the train is a decision AP or not according to the MAC address and the MAC address of the other vehicle-mounted AP carried in the second negotiation message when the second negotiation message broadcasted by the other vehicle-mounted AP on the train where the train is positioned after being electrified is received;

the first processing module is used for determining the main AP, working on a Mesh link established between the main processing module and the determined main trackside AP, establishing Socket connection with the other vehicle-mounted AP and informing the other vehicle-mounted AP of being a standby AP when the judgment result of the judging module is yes;

the acquisition module is used for acquiring locally recorded MAC addresses of all first trackside APs with the signal intensity not less than a set threshold value scanned by the acquisition module in the set period, first timestamps when the MAC addresses of all first trackside APs are scanned by the acquisition module in each first trackside AP, MAC addresses of all second trackside APs with the signal intensity not less than the set threshold value scanned by the other vehicle-mounted AP and second timestamps when the MAC addresses of all second trackside APs are received by the acquisition module in each second trackside AP, wherein the MAC addresses of all the first trackside APs are transmitted by the other vehicle-mounted AP in the set period;

the determining module is used for determining the self running role according to the obtained MAC addresses and all first time stamps of all the first trackside APs, and the obtained MAC addresses and all second time stamps of all the second trackside APs;

the first switching module is used for informing the other vehicle-mounted AP to be upgraded to a main AP and degrading the vehicle-mounted AP to a standby AP if the operation role determined by the determining module is the vehicle head AP, disconnecting the currently working Mesh link, and not performing any operation if the operation role determined by the determining module is the vehicle head AP;

and the second switching module is used for not performing any operation if the determined running role is the tail AP, and informing the other vehicle-mounted AP to degrade into the standby AP and upgrade the other vehicle-mounted AP into the main AP to work on a Mesh link established between the second switching module and the currently determined main trackside AP if the second switching module is the main AP.

The technical scheme provided by the embodiment of the application can have the following beneficial effects:

in the embodiment of the application, two vehicle-mounted APs deployed on a train negotiate a decision AP through negotiation messages broadcast by each other, and initially, the decision AP serves as a main AP, a Socket connection is established between the decision AP and another vehicle-mounted AP, and the other vehicle-mounted AP is informed of being a standby AP; then, the decision AP decides an operation role (a head AP or a tail AP) of the decision AP according to a set period and based on a first timestamp recorded locally when at least one MAC address of a first trackside AP with the signal intensity not less than a set threshold value scanned by the decision AP in the set period and the first timestamp recorded locally when the decision AP scans each first trackside AP, and a second timestamp sent by another vehicle-mounted AP, when the decision AP receives the MAC address of each second trackside AP, and at least one MAC address scanned by another vehicle-mounted AP in the set period and the second timestamp recorded when the decision AP scans each second trackside AP; and finally, deciding whether the main/standby switching is needed or not based on the operation role.

According to the main/standby switching mode, the main/standby switching is automatically realized by the decision AP, development of corresponding vehicle-mounted systems by research personnel is not needed, and network deployment cost is greatly saved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

Fig. 1 is a schematic flowchart of a main/standby switching method according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of a Mesh networking according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a main/standby switching device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. Depending on the context, the words "if" or "if" as used herein may be interpreted as "at" \8230; \8230when "or" when 8230; \8230when ".

Next, examples of the present application will be described in detail.

An embodiment of the present application provides a method for switching between a master and a slave, where the method is applied to a vehicle-mounted AP, and as shown in fig. 1, the method may include the following steps:

s11, after power-on, broadcasting a first negotiation message carrying the MAC address of the user.

S12, when a second negotiation message broadcasted after another vehicle-mounted AP on the train where the vehicle-mounted AP is located is powered on is received, whether the vehicle-mounted AP is a decision AP or not is judged according to the MAC address of the vehicle-mounted AP and the MAC address of the another vehicle-mounted AP carried in the second negotiation message; if yes, executing step S13 to step S16, or executing step S13, step 14, step S15 and step S17; when the determination result is no, step S18 is executed.

And S13, determining the AP as a main AP, working on a Mesh link established between the AP and the determined main trackside AP, establishing Socket connection with another vehicle-mounted AP, and informing the other vehicle-mounted AP of being a standby AP.

S14, according to a set period, acquiring the MAC addresses of all first trackside APs, which are scanned by the local recording in the set period and have the signal intensity not less than a set threshold value, the first time stamps when the MAC addresses of all first trackside APs are scanned by the local recording, the MAC addresses of all second trackside APs, which are scanned by another vehicle-mounted AP and have the signal intensity not less than the set threshold value, and the second time stamps when the MAC addresses of all second trackside APs are received by the local recording.

And S15, determining the operation role of the self according to the acquired MAC addresses and all the first time stamps of all the first trackside APs, and the acquired MAC addresses and all the second time stamps of all the second trackside APs.

And S16, when the determined operation role is the head AP, if the self is the main AP, informing another vehicle-mounted AP to upgrade to the main AP, degrading the self to the standby AP, disconnecting the currently working Mesh link, and if the self is the standby AP, not performing any operation.

And S17, when the determined running role is the tail AP, if the self is the main AP, no operation is performed, if the self is the standby AP, another vehicle-mounted AP is informed to be degraded into the standby AP, the self is upgraded into the main AP, and the main AP works on a Mesh link established between the self and the currently determined main trackside AP.

S18, waiting for another vehicle-mounted AP to establish Socket connection with the other vehicle-mounted AP, sending the MAC address of the second trackside AP with the scanned signal intensity not less than a set threshold value to the other vehicle-mounted AP when the other vehicle-mounted AP establishes the Socket connection with the other vehicle-mounted AP and is informed of the other vehicle-mounted AP to be a standby AP, upgrading the other vehicle-mounted AP to be a main AP when the other vehicle-mounted AP informs that the other vehicle-mounted AP upgrades the other vehicle-mounted AP to be the main AP, working on a Mesh link established between the other vehicle-mounted AP and the currently determined main trackside AP, or degrading the other vehicle-mounted AP to be the standby AP when the other vehicle-mounted AP informs that the other vehicle-mounted AP degrades the other vehicle-mounted AP to be the standby AP, and disconnecting the currently working Mesh link.

It should be noted that, in this embodiment, after the vehicle-mounted AP performs the step S11, another subsequent vehicle-mounted AP may receive the first negotiation message, and a subsequent processing flow is similar to a processing flow after the vehicle-mounted AP receives the second negotiation message, and details are not described here.

Specifically, in step S12, the vehicle-mounted AP may determine whether itself is the decision AP by:

judging whether the MAC address of the vehicle-mounted AP is larger than the MAC address of the other vehicle-mounted AP carried in the second negotiation message;

if so, determining the self as a decision AP;

and when the judgment result is negative, determining that the AP is not a decision AP.

It should be noted that, in this embodiment of the present application, the first negotiation packet and the second negotiation packet may both be data packets or control packets.

In step S13, when establishing a Socket connection with another vehicle-mounted AP, the vehicle-mounted AP may first send a Socket connection request to the another vehicle-mounted AP; and then when receiving a Socket connection response sent by another vehicle-mounted AP, the vehicle-mounted AP determines that Socket connection is successfully established with the other vehicle-mounted AP.

In step S13, when notifying that another vehicle-mounted AP is the standby AP, the vehicle-mounted AP may specifically send a first notification message for indicating that another vehicle-mounted AP is the standby AP to another vehicle-mounted AP through Socket connection, and when receiving the first notification message, another subsequent vehicle-mounted AP determines that the another vehicle-mounted AP is the standby AP.

It should be noted that, in the above step S13, how the on-board AP determines the main trackside AP is a prior art, and a detailed description thereof is omitted here. In the step S14, the set period may be set according to the operation condition of the train where the vehicle-mounted AP is located, for example, the duration of the set period is 1 minute.

In this embodiment, after determining that the vehicle-mounted AP is the master AP, the MAC address of the first trackside AP whose signal strength is not less than the set threshold value and the first timestamp of the first trackside AP scanned by the vehicle-mounted AP are recorded. For example, the in-vehicle AP may record the MAC address of the associated first trackside AP and the associated first timestamp in a list.

For another vehicle-mounted AP, after the AP is determined to be a standby AP, once a second trackside AP with the signal intensity not smaller than a set threshold value is found by the vehicle-mounted AP, the MAC address of the second trackside AP is sent to the vehicle-mounted AP, and the vehicle-mounted AP records the MAC address of the second trackside AP and a second timestamp when the MAC address of the second trackside AP is received. Here, another vehicle-mounted AP may carry the MAC address of the second trackside AP in the notification message, and send the notification message to the vehicle-mounted AP through Socket connection, and the vehicle-mounted AP may also record the MAC address of the relevant second trackside AP and the relevant second timestamp in a list manner.

Thus, once the set period is reached, the vehicle-mounted AP acquires the locally recorded MAC address of at least one first trackside AP, which has a signal intensity not less than the set threshold and is scanned by itself in the set period, the first timestamp when the vehicle-mounted AP scans each first trackside AP, the MAC address of at least one second trackside AP, which has a signal intensity not less than the set threshold and is scanned by itself in the set period and the second timestamp when the vehicle-mounted AP receives the MAC address of each second trackside AP, which are sent by another vehicle-mounted AP, so that the subsequent vehicle-mounted AP can determine its own operation role (a head AP or a tail AP), and perform related main/standby switching operation based on the operation role.

Here, the set threshold may be set by an administrator based on an empirical value and configured in advance to the in-vehicle AP and the another in-vehicle AP.

Specifically, in step S15, the vehicle-mounted AP may determine its own operating role by:

aiming at the MAC address of the currently traversed first trackside AP, judging whether the MAC address of all second trackside APs is the same as the MAC address of the currently traversed first trackside AP or not;

if the judgment result is yes, adding 1 to the role evaluation variable if a first time stamp corresponding to the MAC address of the currently traversed first trackside AP is earlier than a second time stamp corresponding to the MAC address which is the same as the MAC address of the currently traversed first trackside AP in the MAC addresses of all second trackside APs;

if the first time stamp corresponding to the MAC address of the first traversed trackside AP is later than the second time stamp corresponding to the MAC address which is the same as the MAC address of the first traversed trackside AP in all the MAC addresses of the second trackside APs, adding 1 to the role evaluation variable of the other vehicle-mounted AP;

if the judgment result is negative, no operation is performed;

determining the running role of the vehicle-mounted AP according to the role evaluation variable of the vehicle-mounted AP and the role evaluation variable of the vehicle-mounted AP, which are obtained when all the MAC addresses of the first trackside AP are traversed;

and when the MAC address of the currently traversed first trackside AP is the first MAC address, the role evaluation variable of the first trackside AP and the role evaluation variable of the other vehicle-mounted AP are both 0.

Here, the role evaluation variable is mainly used to evaluate the operation role of the corresponding in-vehicle AP.

More specifically, in this determination manner, the vehicle-mounted AP may determine its own operation role by any one of the following manners:

the first mode is as follows: comparing the role evaluation variable of the vehicle-mounted AP with the role evaluation variable of the other vehicle-mounted AP; if the own role evaluation variable is larger than the role evaluation variable of another vehicle-mounted AP, determining the own running role as a vehicle head AP; if the own role evaluation variable is smaller than the role evaluation variable of another vehicle-mounted AP, determining the own running role as a vehicle tail AP; and if the own role evaluation variable is equal to the role evaluation variable of the other vehicle-mounted AP, determining that the own operation role is the same as the operation role determined last time.

The second mode is as follows: calculating a difference value between the role evaluation variable of the vehicle-mounted AP and the role evaluation variable of the other vehicle-mounted AP to obtain a first operation result; carrying out quotient calculation on the first calculation result and the role evaluation variable of the first calculation result to obtain a second calculation result; judging whether the second operation result is not less than a set value; if the judgment result is yes, determining the self operation role as the locomotive AP; and if the judgment result is negative, determining that the self running role is the tail AP.

In the second aspect, the setting value may be set by an administrator according to actual scanning of the in-vehicle AP and another in-vehicle AP, and may be configured in advance in the in-vehicle AP.

It should be further noted that, in this embodiment of the application, after the vehicle-mounted AP performs step S15, in order to save the storage resource of the vehicle-mounted AP, after determining its own operation role, the vehicle-mounted AP may delete the MAC address and the related first timestamp of the relevant first trackside AP, and the MAC address and the related second timestamp of the relevant second trackside AP, which are recorded in the current setting period.

Specifically, in step S16, when notifying that another vehicle-mounted AP is upgraded to the master AP, the vehicle-mounted AP may specifically send, to another vehicle-mounted AP, a second notification message for instructing another vehicle-mounted AP to upgrade to the master AP through Socket connection, and when receiving the second notification message, another subsequent vehicle-mounted AP may upgrade itself to the master AP.

In step S17, when notifying that another vehicle-mounted AP degrades to the standby AP, the vehicle-mounted AP may specifically send, through Socket connection, a third notification message for instructing another vehicle-mounted AP to degrade to the standby AP to the another vehicle-mounted AP, and when receiving the third notification message, another subsequent vehicle-mounted AP may degrade itself to the standby AP.

The following describes the main/standby switching method in detail with reference to a specific embodiment.

As shown in fig. 2, it is assumed that both ends of the train 1 are disposed with the onboard AP1 and the onboard AP2, and the corresponding trackside APs include a trackside AP1, a trackside AP2, a trackside AP3, and a trackside AP4, etc. (only 4 trackside APs are shown in fig. 2).

After being powered on, both the vehicle-mounted AP1 and the vehicle-mounted AP2 broadcast negotiation messages carrying respective MAC addresses.

For example, the vehicle-mounted AP1 broadcasts a negotiation packet 1 carrying its own MAC address (e.g., MAC 1); the vehicle AP2 broadcasts a negotiation packet 2 carrying its own MAC address (e.g., MAC 2). Here, negotiation packet 1 and negotiation packet 2 are both data packets.

Taking the vehicle-mounted AP1 as an example, when receiving the negotiation packet 2 broadcasted by the AP2, it is determined whether the MAC address of the vehicle-mounted AP1 (i.e., MAC 1) is greater than the MAC address of the vehicle-mounted AP2 (i.e., MAC 2) carried in the negotiation packet 2.

If the MAC1 is larger than the MAC2, the judgment result is yes, at this time, the vehicle-mounted AP1 determines that the vehicle-mounted AP1 is a decision-making AP and also determines that the vehicle-mounted AP is a main AP, works on a Mesh link established between the vehicle-mounted AP and the determined main trackside AP, establishes Socket connection with the vehicle-mounted AP2, and informs the vehicle-mounted AP2 of being a standby AP.

Then, the onboard AP1 records the MAC address of the first trackside AP whose signal strength is not less than a set threshold (e.g., 30 DB) and the first timestamp of the first trackside AP scanned by itself.

Assuming that a first set period is reached (for example, the corresponding time duration is 1 minute), the vehicle-mounted AP1 may obtain locally recorded MAC addresses of all first trackside APs whose signal strengths are not less than a set threshold and a first time stamp (as shown in table one below) when the vehicle-mounted AP scans each first trackside AP, and MAC addresses of all second trackside APs whose signal strengths are not less than the set threshold and a second time stamp (as shown in table two below) when the vehicle-mounted AP2 sends the MAC addresses of the second trackside APs whose signal strengths are not less than the set threshold and receives the MAC addresses of each second trackside AP.

Time stamp	MAC address of trackside AP
		09：21：35	Trackside AP1-MAC address
09：21：40	Trackside AP2-MAC address
		09：21：50	Trackside AP3-MAC address

Watch 1

Time stamp	MAC address of trackside AP
		09：21：41	Trackside AP1-MAC address
09：21：49	Trackside AP2-MAC address
		09：21：56	Trackside AP3-MAC address

Watch 2

Here, the MAC addresses of these second trackside APs are transmitted by the onboard AP2 after the Socket connection is established with the onboard AP and notified of itself as a standby AP by the onboard AP 1.

Next, the vehicle-mounted AP1 traverses the MAC addresses in the first table, and each time one MAC address in the first table is traversed, the following operations are performed:

judging whether the MAC address identical to the MAC address traversed currently exists in the second table;

if the judgment result is yes, if a first time stamp corresponding to the currently traversed MAC address is earlier than a second time stamp corresponding to the MAC address which is the same as the currently traversed MAC address in the table II, adding 1 to the role evaluation variable of the user;

if the first timestamp corresponding to the currently traversed MAC address is later than the second timestamp corresponding to the MAC address which is the same as the currently traversed MAC address in the table two, adding 1 to the role evaluation variable of the vehicle-mounted AP 2;

if the judgment result is negative, no operation is performed;

and when the currently traversed MAC address is the first MAC address, the role evaluation variable of the vehicle-mounted AP1 and the role evaluation variable of the vehicle-mounted AP2 are both 0.

After traversing all the MAC addresses in the table one, the vehicle-mounted AP1 may obtain that its role evaluation variable is 3, and the role evaluation variable of the vehicle-mounted AP2 is 0.

The vehicle-mounted AP1 can compare the role evaluation variable of the vehicle-mounted AP1 with the role evaluation variable of the vehicle-mounted AP2, the comparison result is that the role evaluation variable of the vehicle-mounted AP is larger than the role evaluation variable of the vehicle-mounted AP2, at the moment, the vehicle-mounted AP1 is determined to be a vehicle head AP, the first table and the second table are deleted, and the vehicle-mounted AP1 is a main AP, so that the vehicle-mounted AP1 can inform the vehicle-mounted AP2 of being upgraded to be the main AP, degrade the vehicle-mounted AP to be a standby AP, and disconnect a Mesh link which works at present.

Subsequently, it is assumed that a certain set period is reached, and it is assumed that the vehicle-mounted AP1 determines that its own operation role is the car tail AP according to the acquired locally recorded MAC addresses of all first trackside APs whose signal strengths are not less than the set threshold and the first time stamp when it scans each first trackside AP, and the acquired MAC addresses of all second trackside APs whose signal strengths are not less than the set threshold and the second time stamp when it receives the MAC address of each second trackside AP, which are scanned by the vehicle-mounted AP2 and sent by the vehicle-mounted AP2 in the set period, so that the vehicle-mounted AP1 deletes the relevant MAC address and the relevant time stamp recorded in the period, and if it is the standby AP, the vehicle-mounted AP1 notifies the vehicle-mounted AP2 to degrade into the standby AP and upgrades itself into the main AP, and works on the Mesh link established between itself and the currently determined main trackside AP.

According to the technical scheme, in the embodiment of the application, two vehicle-mounted APs deployed on a train negotiate a decision AP through negotiation messages broadcast by each other, and initially, the decision AP serves as a main AP, a Socket connection is established between the decision AP and the other vehicle-mounted AP, and the other vehicle-mounted AP is informed of being a standby AP; then, the decision AP decides the operation role (a head AP or a tail AP) of the decision AP according to a set period and based on the locally recorded MAC address of at least one first trackside AP with the signal intensity not less than a set threshold value scanned in the set period by the decision AP, a first time stamp when the decision AP scans each first trackside AP, at least one MAC address of a second trackside AP with the signal intensity not less than the set threshold value scanned in the set period by another vehicle-mounted AP and a second time stamp when the decision AP receives the MAC address of each second trackside AP; and finally, deciding whether the main/standby switching is needed or not based on the operation role.

In the master-slave switching mode, the decision AP automatically realizes the master-slave switching without developing a corresponding vehicle-mounted system by research personnel, so that the network deployment cost is greatly saved.

Based on the same inventive concept, the present application further provides a main/standby switching device, where the device is applied to a vehicle-mounted AP, and a schematic structural diagram of the device is shown in fig. 3, and specifically includes:

the broadcasting module 31 is configured to broadcast a first negotiation packet carrying an own MAC address after being powered on;

the determining module 32 is configured to, when receiving a second negotiation packet broadcasted after another vehicle-mounted AP on the train where the determining module is located is powered on, determine whether the determining module is a decision AP according to the MAC address and an MAC address of the another vehicle-mounted AP carried in the second negotiation packet;

the first processing module 33 is configured to, when the determination result of the determining module is yes, determine that the AP is a main AP, work on a Mesh link established between the AP and the determined main trackside AP, establish Socket connection with the another vehicle-mounted AP, and notify the another vehicle-mounted AP of being a standby AP;

an obtaining module 34, configured to obtain, according to a set period, locally recorded MAC addresses of all first trackside APs whose signal strengths are not less than a set threshold and scanned in the set period, a first timestamp when each first trackside AP is scanned by itself, and MAC addresses of all second trackside APs whose signal strengths are not less than the set threshold and scanned by another vehicle-mounted AP and sent by the another vehicle-mounted AP in the set period, and a second timestamp when each second trackside AP receives the MAC address of each second trackside AP;

the determining module 35 is configured to determine an operation role of the determining module according to the acquired MAC addresses and all first timestamps of all first trackside APs, and the acquired MAC addresses and all second timestamps of all second trackside APs;

a first switching module 36, configured to, when the operation role determined by the determination module is a vehicle head AP, notify the other vehicle-mounted AP to upgrade to a main AP if the vehicle-mounted AP is a main AP, degrade the vehicle-mounted AP to a standby AP, disconnect a currently-operating Mesh link, and if the vehicle-mounted AP is a standby AP, do nothing;

and a second switching module 37, configured to, when the determined running role is the car tail AP, perform no operation if the own vehicle is the main AP, and if the own vehicle is the standby AP, notify the another vehicle-mounted AP to degrade into the standby AP, upgrade the own vehicle-mounted AP into the main AP, and work on a Mesh link established between the own vehicle-mounted AP and the currently determined main trackside AP.

Preferably, the determining module 32 is specifically configured to determine whether itself is a decision AP by:

judging whether the MAC address is larger than the MAC address of the other vehicle-mounted AP carried in the second negotiation message;

if so, determining the self as a decision AP;

Preferably, the apparatus further comprises:

a second processing module (not shown in fig. 3), configured to wait for the another vehicle-mounted AP to establish Socket connection with itself when a determination result of the determining module is negative; after a Socket connection is established with the other vehicle-mounted AP and the other vehicle-mounted AP informs that the other vehicle-mounted AP is a standby AP, sending the MAC address of the second trackside AP, the signal intensity of which is scanned by the other vehicle-mounted AP is not less than the set threshold value, to the other vehicle-mounted AP; and when being notified of upgrading to the main AP by the other vehicle-mounted AP, the other vehicle-mounted AP upgrades the other vehicle-mounted AP to the main AP and works on a Mesh link established between the other vehicle-mounted AP and the currently determined main trackside AP, or when being notified of degrading to the standby AP by the other vehicle-mounted AP, the other vehicle-mounted AP degrades the other vehicle-mounted AP to the standby AP and disconnects the currently working Mesh link.

Preferably, the determining module 35 is specifically configured to:

judging whether an MAC address identical to the MAC address of the currently traversed first trackside AP exists in the MAC addresses of all second trackside APs aiming at the MAC address of the currently traversed first trackside AP;

if the first timestamp corresponding to the MAC address of the currently traversed first trackside AP is later than a second timestamp corresponding to the MAC address which is the same as the MAC address of the currently traversed first trackside AP in the MAC addresses of all second trackside APs, adding 1 to the role evaluation variable of the other vehicle-mounted AP;

if the judgment result is negative, no operation is carried out;

determining the running role of the other vehicle-mounted AP according to the role evaluation variable of the other vehicle-mounted AP and the role evaluation variable of the other vehicle-mounted AP, which are obtained when all the MAC addresses of the first trackside APs are traversed;

Preferably, the determining module 35 is specifically configured to:

comparing the role evaluation variable of the vehicle-mounted AP with the role evaluation variable of the other vehicle-mounted AP;

if the comparison result is that the role evaluation variable of the vehicle-mounted AP is larger than the role evaluation variable of the other vehicle-mounted AP, the running role of the vehicle-mounted AP is determined to be the vehicle head AP;

if the comparison result is that the own role evaluation variable is smaller than the role evaluation variable of the other vehicle-mounted AP, determining the own running role as the vehicle tail AP;

and if the comparison result is that the own role evaluation variable is equal to the role evaluation variable of the other vehicle-mounted AP, determining that the own operation role is the same as the operation role determined last time.

Preferably, the determining module 35 is specifically configured to:

calculating a difference value between the role evaluation variable of the vehicle-mounted AP and the role evaluation variable of the other vehicle-mounted AP to obtain a first operation result;

carrying out quotient calculation on the first calculation result and the own role evaluation variable to obtain a second calculation result;

judging whether the second operation result is not less than a set value;

if the judgment result is yes, determining the self operation role as the locomotive AP;

and if the judgment result is negative, determining that the self running role is the tail AP.

According to the technical scheme, in the embodiment of the application, two vehicle-mounted APs deployed on a train negotiate out a decision AP through negotiation messages broadcasted from each other, and initially, the decision AP serves as a main AP, a Socket connection is established between the decision AP and the other vehicle-mounted AP, and the other vehicle-mounted AP is informed of being a standby AP; then, the decision AP decides the operation role (a head AP or a tail AP) of the decision AP according to a set period and based on the locally recorded MAC address of at least one first trackside AP with the signal intensity not less than a set threshold value scanned in the set period by the decision AP, a first time stamp when the decision AP scans each first trackside AP, at least one MAC address of a second trackside AP with the signal intensity not less than the set threshold value scanned in the set period by another vehicle-mounted AP and a second time stamp when the decision AP receives the MAC address of each second trackside AP; and finally, deciding whether the main/standby switching is needed or not based on the operation role.

An electronic device is further provided in the embodiments of the present application, as shown in fig. 4, and includes a processor 41 and a machine-readable storage medium 42, where the machine-readable storage medium 42 stores machine-executable instructions that can be executed by the processor 41, and the processor 41 is caused by the machine-executable instructions to: and implementing the main/standby switching method.

The machine-readable storage medium may include a Random Access Memory (RAM) and a Non-Volatile Memory (NVM), such as at least one disk Memory. Alternatively, the machine-readable storage medium may be at least one memory device located remotely from the processor.

The Processor may be a general-purpose Processor, including a Central Processing Unit (CPU), a Network Processor (NP), and the like; but also Digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs) or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components.

In another embodiment provided by the present application, a computer-readable storage medium is further provided, where a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned active/standby switching method are implemented.

The above description is only a preferred embodiment of the present application and should not be taken as limiting the present application, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A main/standby switching method is applied to a vehicle-mounted AP, and comprises the following steps:

when a second negotiation message broadcasted by another vehicle-mounted AP on the train where the vehicle-mounted AP is located after being electrified is received, judging whether the vehicle-mounted AP is a decision AP or not according to the MAC address and the MAC address of the another vehicle-mounted AP carried in the second negotiation message;

determining the operation role of the system according to the obtained MAC addresses and the first time stamps of all the first trackside APs, the MAC addresses and the second time stamps of all the second trackside APs;

when the determined operation role is the locomotive AP, if the mobile terminal is the main AP, informing the other vehicle-mounted AP of upgrading to the main AP, degrading the mobile terminal to the standby AP, disconnecting the currently working Mesh link, and if the mobile terminal is the standby AP, not doing any operation;

and when the determined running role is the tail AP, if the self is the main AP, no operation is performed, if the self is the standby AP, the other vehicle-mounted AP is informed to be degraded into the standby AP, the self is upgraded into the main AP, and the main AP works on a Mesh link established between the self and the currently determined main trackside AP.

2. The method of claim 1, wherein determining whether the AP is the decision AP is performed by:

if so, determining the self as a decision AP;

3. The method according to claim 1 or 2, characterized in that the method further comprises:

if not, waiting for the other vehicle-mounted AP to establish Socket connection with the other vehicle-mounted AP;

after a Socket connection is established with the other vehicle-mounted AP and the other vehicle-mounted AP informs that the other vehicle-mounted AP is a standby AP, sending the MAC address of the second trackside AP, the signal intensity of which is scanned by the other vehicle-mounted AP is not less than the set threshold value, to the other vehicle-mounted AP;

when the other vehicle-mounted AP informs that the AP is upgraded to the main AP, the other vehicle-mounted AP upgrades the AP to the main AP and works on a Mesh link established between the other vehicle-mounted AP and the currently determined main trackside AP, or,

and when the other vehicle-mounted AP informs that the self is degraded to the standby AP, and the currently working Mesh link is disconnected.

4. The method according to claim 1, wherein determining the operating role of the AP according to the obtained MAC addresses and all first timestamps of all first trackside APs and the obtained MAC addresses and all second timestamps of all second trackside APs specifically comprises:

if the judgment result is negative, no operation is performed;

5. The method according to claim 4, wherein determining the operating role of the vehicle-mounted AP according to the own role evaluation variable obtained when all MAC addresses of the first trackside AP are traversed and the role evaluation variable of the another vehicle-mounted AP, specifically includes:

if the comparison result is that the own role evaluation variable is larger than the role evaluation variable of the other vehicle-mounted AP, determining the own running role as the vehicle head AP;

6. The method according to claim 4, wherein determining the operating role of the vehicle-mounted AP according to the own role evaluation variable obtained when all MAC addresses of the first trackside AP are traversed and the role evaluation variable of the another vehicle-mounted AP, specifically includes:

calculating a difference value between the own role evaluation variable and the role evaluation variable of the other vehicle-mounted AP to obtain a first operation result;

judging whether the second operation result is not less than a set value;

and if the judgment result is negative, determining that the self running role is the vehicle tail AP.

7. A master-slave switching device is characterized in that the device is applied to a vehicle-mounted AP, and the device comprises:

the judging module is used for judging whether the train is a decision AP or not according to the MAC address and the MAC address of another vehicle-mounted AP carried in a second negotiation message when the second negotiation message broadcasted by another vehicle-mounted AP on the train where the train is positioned after being electrified is received;

and the second switching module is used for not performing any operation if the determined running role is the tail AP, informing the other vehicle-mounted AP of degrading into the standby AP if the determined running role is the main AP, upgrading the vehicle-mounted AP into the main AP and working on a Mesh link established between the vehicle-mounted AP and the currently determined main trackside AP.

8. The apparatus according to claim 7, wherein the determining module is specifically configured to determine whether the AP is a decision AP by:

if so, determining the self as a decision AP;

9. The apparatus of claim 7 or 8, further comprising:

the second processing module is used for waiting for the other vehicle-mounted AP to establish Socket connection with the second processing module when the judgment result of the judgment module is negative; after a Socket connection is established with the other vehicle-mounted AP and the other vehicle-mounted AP informs that the other vehicle-mounted AP is a standby AP, sending the MAC address of the second trackside AP, the signal intensity of which is scanned by the other vehicle-mounted AP is not less than the set threshold value, to the other vehicle-mounted AP; and when being notified of upgrading to the main AP by the other vehicle-mounted AP, the other vehicle-mounted AP upgrades the other vehicle-mounted AP to the main AP and works on a Mesh link established between the other vehicle-mounted AP and the currently determined main trackside AP, or when being notified of degrading to the standby AP by the other vehicle-mounted AP, the other vehicle-mounted AP degrades the other vehicle-mounted AP to the standby AP and disconnects the currently working Mesh link.

10. The apparatus of claim 7, wherein the determining module is specifically configured to:

if the judgment result is negative, no operation is performed;

determining the operation role of the vehicle-mounted AP according to the role evaluation variable of the vehicle-mounted AP and the role evaluation variable of the other vehicle-mounted AP, which are obtained when all MAC addresses of the first trackside AP are traversed;

when the MAC address of the first traversed trackside AP is the first MAC address, the role evaluation variable of the first traversed trackside AP and the role evaluation variable of the other vehicle-mounted AP are both 0.

11. The apparatus of claim 10, wherein the determining module is specifically configured to:

12. The apparatus of claim 10, wherein the determining module is specifically configured to:

judging whether the second operation result is not less than a set value;