CN110809251B

CN110809251B - Switching method and device of wireless access point

Info

Publication number: CN110809251B
Application number: CN201910958040.XA
Authority: CN
Inventors: 陈航
Original assignee: Ruijie Networks Co Ltd
Current assignee: Ruijie Networks Co Ltd
Priority date: 2019-10-10
Filing date: 2019-10-10
Publication date: 2022-08-19
Anticipated expiration: 2039-10-10
Also published as: CN110809251A

Abstract

The invention discloses a switching method and a switching device of a wireless access point, which are used for improving the connection accuracy of a vehicle-mounted AP and a ground AP in a quick roaming process and improving the communication quality. The switching method of the wireless access point comprises the following steps: the mobile AP receives a first message from first equipment, wherein the first message carries a first identifier of second equipment, and the first identifier is acquired by the first equipment from the second equipment in a near field communication mode; the mobile AP sends a first message to the server, wherein the first message is used for indicating a second identifier of at least one ground AP corresponding to the first identifier and the signal strength of each ground AP, and the at least one ground AP is an AP of which the distance between the at least one ground AP and the second equipment is smaller than a second threshold value; the mobile AP receives a second message from the server, wherein the second message comprises a second identifier of a first target AP, and the first target AP is an AP with the strongest signal strength in at least one ground AP; the mobile AP establishes a connection with the first target AP.

Description

Switching method and device of wireless access point

Technical Field

The present invention relates to the field of wireless communications technologies, and in particular, to a method and an apparatus for switching a wireless access point.

Background

Since a coverage area of a wireless Access Point (AP), commonly referred to as a hotspot, is limited, when the mobile terminal is far away from the AP, the communication quality may be degraded. Therefore, in order to improve communication quality, a plurality of APs may be deployed, and when a mobile terminal is far from an AP, the mobile terminal may disconnect from the AP and establish a connection with a closer AP in a shorter time. The process of a mobile terminal switching from a connection with one AP to another is called roaming.

Fast roaming means that the time required for connection re-establishment when a mobile terminal is handed over from one AP to another AP is short, e.g. less than 50 ms. For example, in one application scenario, an AP is provided on a vehicle, and the AP may switch from one AP to another AP of a plurality of APs deployed, for example, in a tunnel, to obtain the best communication quality. For convenience of description, an AP provided on a vehicle is referred to as an on-board AP, and a plurality of APs disposed in, for example, a tunnel is referred to as a ground AP. Since the speed of the vehicle is high in the running process, the vehicle-mounted AP needs to frequently switch the ground AP connected with the vehicle-mounted AP in a short time, that is, fast roaming needs to be realized.

In the prior art, when a vehicle-mounted AP needs to roam quickly, a ground AP which responds preferentially is usually selected from a plurality of ground APs to connect, but the ground AP which responds preferentially may not be a more accurate ground AP. For example, the ground AP that responds preferentially may be a ground AP that is farther away from the onboard AP or a ground AP in a reverse orbit, resulting in poor communication quality and even roaming failure.

Therefore, the problem of low communication quality exists when the current vehicle-mounted AP is switched among a plurality of ground APs.

Disclosure of Invention

The embodiment of the invention provides a switching method and a switching device of a wireless access point, which are used for improving the communication quality of a vehicle-mounted AP and a ground AP in a rapid roaming process.

In a first aspect, an embodiment of the present invention provides a method for switching a wireless access point, where the method includes:

a mobile AP receives a first message from a first device, wherein the first message carries a first identifier of a second device, the distance between the mobile AP and the first device is smaller than a first threshold value, and the first identifier is acquired by the first device from at least one second device in a short-distance communication mode in the moving process;

the mobile AP sends a first message to a server, wherein the first message is used for indicating a second identifier of at least one ground AP corresponding to the first identifier and the signal strength of each ground AP, and the at least one ground AP is an AP of which the distance between the at least one ground AP and the second equipment is smaller than a second threshold value;

the mobile AP receives a second message from the server, wherein the second message comprises a second identifier of a first target AP, and the first target AP is an AP with the strongest signal strength in the at least one ground AP;

and the mobile AP establishes connection with the first target AP.

In the embodiment of the present invention, the first device may acquire the first identifier of the second device through a short-range communication method. If the first device acquires the first identity, the first device is closer to the second device, i.e. the location of the first device may be approximated by the location of the second device. And the location of the first device may be approximated as the location of the mobile AP, then the location of the mobile AP may be approximated as the location of the second device, such that at least one terrestrial AP within a certain range from the second device may be considered as at least one terrestrial AP within a certain range from the mobile AP. And then the mobile AP sends the first message to the server, wherein the first message can represent the corresponding relation between the first identifier, the second identifier of the at least one ground AP and the corresponding signal strength, so that the server can determine the ground AP which is closer to the mobile AP and has stronger signal strength from the at least one ground AP, namely, determine a first target AP, and the first target AP can be considered as an AP which is more adaptive to the mobile AP from the at least one ground AP. Then the mobile AP establishes a connection with the first target AP and the communication quality is high.

Optionally, before the mobile AP receives the first message from the first device, the method further includes:

the mobile AP receives a first instruction, wherein the first instruction is used for instructing the mobile AP to switch the working mode into a non-root bridge mode, and the non-root bridge mode is used for representing that the mobile AP can receive data output by external equipment;

and the mobile AP switches the working mode into the non-root bridge mode according to the first instruction.

Considering that the operation mode of the mobile AP includes a root bridge mode and a non-root bridge mode, in the embodiment of the present invention, the operation mode of the mobile AP may be switched to the non-root bridge mode in advance. Therefore, the mobile AP can passively receive information from external equipment, for example, the information is intercepted from the ground AP and the ground AP with stronger signal strength is favorably found out by the mobile AP, namely the AP which is more adaptive to the mobile AP in at least one ground AP.

Optionally, the method further includes:

if the mobile AP fails to connect with the first target AP, the mobile AP sends a first prompt message to the server;

the mobile AP receiving a third message from the server, the third message including a second identification of a second target AP, wherein the signal strength of the second target AP is strongest among the at least one terrestrial AP except the first target AP;

the mobile AP connects with the second target AP.

In the embodiment of the invention, when the mobile AP fails to connect with the first target AP, the mobile AP may request the server to select again a ground AP which is close to the mobile AP and has strong signal strength from the surrounding ground APs except for the first target AP, and the mobile AP connects with the ground AP selected again by the server, so as to ensure good communication quality as much as possible.

Optionally, the method further includes:

the mobile AP determines that the first target AP is different from the historical target AP corresponding to the second device;

and the mobile AP sends second prompt information to the server, wherein the second prompt information is used for prompting that the historical target AP breaks down.

In this embodiment of the present invention, the historical target AP may be considered as the most suitable AP for a certain second device to connect when the mobile AP is close to the second device. In general, the historical target AP is the same AP, and for the second device, if the first target AP determined multiple times is not the historical target AP, the historical target AP may have failed. At this time, the mobile AP can inform the server, so that the directional maintenance is convenient to realize.

In a second aspect, an embodiment of the present invention provides a server, where the server includes:

a server receives a first message from a mobile AP, wherein the first message is used for indicating a second identifier of at least one ground AP corresponding to a first identifier of a second device and the signal strength of each ground AP, the first identifier is an identifier which is obtained by the first device from the at least one second device in a short-distance communication mode in a moving process and is sent to the mobile AP, and the at least one ground AP is an AP of which the distance between the at least one ground AP and the second device is smaller than a second threshold value;

the server determines a first target AP from the at least one ground AP according to the first message, wherein the first target AP is an AP with the strongest signal strength in the at least one ground AP;

and the server sends a first message to the mobile AP, wherein the first message comprises a second identification of a first target AP so that the mobile AP can establish connection with the first target AP.

In the embodiment of the present invention, the server performs screening on at least one ground AP included in the first message according to a preset screening rule, so as to determine an AP which is closer to the mobile AP and has a stronger signal strength, that is, determine a first target AP, where the first target AP may be considered as an AP that is more suitable for the mobile AP in the at least one ground AP. And then the server sends the identification of the first target AP to the mobile AP, so that the mobile AP can quickly establish connection with the first target AP, quick roaming is realized, and good communication quality is obtained.

Optionally, the determining, by the server, the first target AP from the at least one ground AP according to the first message includes:

the server screens the at least one ground AP according to a preset rule to obtain at least one target AP;

the server determines the first target AP from the at least one target AP.

In the embodiment of the invention, the server can screen out part of unreasonable ground APs in at least one ground AP according to a preset rule, such as ground APs far away from the mobile AP or ground APs positioned on different track sides, so that the mobile AP can establish connection with an AP which is close to the ground AP and has a strong signal as far as possible. That is, the mobile AP establishes a connection with a better adapted AP of the at least one terrestrial AP, thereby obtaining a good communication quality.

Optionally, the method further includes:

and the server screens the at least one ground AP according to the first message and a plurality of historical first messages to obtain the at least one target AP.

In the embodiment of the invention, the server combines the current first message and the plurality of historical messages to screen at least one ground AP, so that the situation that the ground AP with stronger actual signal strength, namely the ground AP which is actually matched with the mobile AP is screened out due to unreasonable setting of the screening rule is avoided, and the screening accuracy is improved.

Optionally, the method further includes:

the server receives second prompt information from the mobile AP, wherein the second prompt information is used for prompting the server that the historical target AP fails;

and if the server determines that the number of times of the received second prompt message exceeds a first threshold value, outputting alarm information, wherein the alarm information is used for prompting maintenance personnel that the historical target AP fails.

In the embodiment of the invention, if the server determines that the number of times of the second prompt message exceeds the first threshold, the server may determine that the historical target AP may have a fault, and at this time, the server outputs the third prompt message, which is convenient for operation and maintenance personnel to locate the faulty AP.

In a third aspect, an embodiment of the present invention provides a wireless access point AP, where the AP includes:

a receiving module, configured to receive a first message from a first device, where the first message carries a first identifier of a second device, a distance between the AP and the first device is smaller than a first threshold, and the first identifier is obtained by the first device from at least one second device in a near field communication manner during a moving process;

a sending module, configured to send a first message to a server, where the first message is used to indicate a second identifier of at least one ground AP corresponding to the first identifier and a signal strength of each ground AP, and the at least one ground AP is an AP whose distance from the second device is smaller than a second threshold;

the receiving module is further configured to receive a second message from the server, where the second message includes a second identifier of a first target AP, and the first target AP is an AP with the strongest signal strength among the at least one ground AP;

a connection module, configured to establish a connection with the first target AP.

Optionally, the system further comprises a switching module;

wherein, the receiving module is further configured to: receiving a first instruction, wherein the first instruction is used for instructing the mobile AP to switch a working mode into a non-root bridge mode, and the non-root bridge mode is used for representing that the mobile AP can receive data output by an external device;

and the switching module is used for switching the working mode into the non-root bridge mode according to the first instruction.

Optionally, the sending module is further configured to send a first prompt message to the server when the connection between the wireless access point and the first target AP fails;

the receiving module is further configured to receive a third message from the server, the third message including a second identification of a second target AP, wherein a signal strength of the second target AP is strongest among the at least one terrestrial AP except for the first target AP;

a connection module, configured to connect to the second target AP.

Optionally, the determining module is further configured to determine that the historical target APs corresponding to the first target AP and the second device are different;

the sending module is further configured to send second prompt information to the server, where the second prompt information is used to prompt the history target AP that the AP has failed.

In a fourth aspect, an embodiment of the present invention provides a server, where the server includes:

a receiving module, configured to receive a first message from a mobile AP, where the first message is used to indicate a second identifier of at least one ground AP corresponding to a first identifier of a second device and a signal strength of each ground AP, where the first identifier is an identifier obtained by a first device from the at least one second device in a short-distance communication manner during a moving process and sent to the mobile AP, and the at least one ground AP is an AP where a distance between the second devices is smaller than a second threshold;

a confirmation module, configured to determine a first target AP from the at least one ground AP according to the first message, where the first target AP is an AP with the strongest signal strength among the at least one ground AP;

a sending module, configured to send a first message to the mobile AP, where the first message includes a second identifier of a first target AP, so that the mobile AP establishes a connection with the first target AP.

Optionally, the confirmation module is specifically configured to:

screening the at least one ground AP according to a preset rule to obtain at least one target AP;

determining the first target AP from the at least one target AP.

Optionally, the confirming module is further configured to:

and screening the at least one ground AP according to the first message and a plurality of historical first messages to obtain the at least one target AP.

Optionally, the receiving module is further configured to receive second prompt information from the mobile AP, where the second prompt information is used to prompt the server that the historical target AP fails;

the determining module is further configured to output alarm information if it is determined that the number of times of receiving the first prompt information exceeds a first threshold, where the alarm information is used to prompt a maintenance person that the historical target AP has failed.

In a fifth aspect, an embodiment of the present invention provides a wireless access point AP, where the AP includes a processor and a memory, and the processor is configured to implement the steps of the method according to the first aspect when executing a computer program stored in the memory.

In a sixth aspect, an embodiment of the present invention provides a server, where the server includes a processor and a memory, and the processor is configured to execute a computer program stored in the memory to implement the steps of the method according to the second aspect.

In a seventh aspect, an embodiment of the present invention provides a communication system, where the communication system includes an AP according to the third aspect, a server according to the fourth aspect, a first device, a second device, and at least one terrestrial AP, where a distance between the AP and the first device is smaller than a first threshold, the first device communicates with the second device through a short-range communication method, and the at least one terrestrial AP is an AP whose distance between the AP and the second device is smaller than a second threshold.

In an eighth aspect, embodiments of the present invention provide a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of the method according to the embodiments of the first aspect or the second aspect.

Drawings

Fig. 1 is a schematic distribution diagram of subway rail equipment provided in an embodiment of the present invention;

fig. 2 is a flowchart of a method for switching a wireless access point according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a wireless access point according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a server provided in an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a wireless access point according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a server provided in the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described below in detail and completely with reference to the accompanying drawings of the embodiments of the present disclosure.

With the gradual expansion of wireless network applications, users have increasingly high mobility requirements for accessing networks. Because the coverage area of one AP is limited, when the mobile terminal is far away from the AP, the communication quality will be degraded, and at this time, the mobile terminal will switch from the AP to another AP and establish a connection with another AP, so as to ensure that the service performed by the mobile terminal is not interrupted. For example, a user takes a subway, a vehicle-mounted AP is arranged on the subway, a plurality of ground APs are arranged around a track where the subway runs, and the vehicle-mounted AP moves along with the running of the subway, and for convenience of description, the vehicle-mounted AP is hereinafter referred to as a mobile AP. In contrast, the terrestrial AP is referred to as a terrestrial AP. And switching among a plurality of ground APs to ensure the communication quality. Usually, the subway runs fast, and therefore the vehicle-mounted AP is required to be rapidly switched among a plurality of ground APs.

The current method for implementing fast handoff is to select the terrestrial AP that responds preferentially to connect with the mobile AP, but the terrestrial AP that responds preferentially may not be the preferred terrestrial AP. For example, the ground AP which responds preferentially may be a ground AP which is far away from the vehicle-mounted AP, and then the communication quality is poor after the mobile AP establishes a connection with the ground AP which responds preferentially. For another example, the ground AP with a preferential response may be a ground AP of a reverse track, and the mobile AP and the ground AP with the preferential response also have low communication quality and even fail to connect, where the ground AP of the reverse track refers to a ground AP on the other track side opposite to the track where the current subway is located.

In view of this, an embodiment of the present invention provides a method for switching a wireless access point, in which a mobile AP may select at least one ground AP closer to the mobile AP from a plurality of ground APs, and then select a ground AP with the strongest signal strength from the at least one ground AP for connection, where the ground AP may be considered as an AP more adapted to the mobile AP, that is, after the mobile AP establishes a connection with the ground AP, the communication quality is higher, thereby improving user experience.

For ease of understanding, an application scenario of the embodiment of the present invention is first described. Fig. 1 is a schematic view of an application scenario according to an embodiment of the present invention. Included in fig. 1 are a mobile AP101, a plurality of terrestrial APs 102, a first device 103, a plurality of second devices 104, and a server 105. The mobile AP101 may be disposed on a mobile device, such as a subway. The first device 103 may be a Radio Frequency Identification (RFID) reader, and the distance between the mobile AP101 and the first device 103 is smaller than a first threshold, for example, the first device 103 may be disposed on a subway, so that the position of the first device 103 may be identical to the position of the mobile AP 101. A plurality of terrestrial APs 102 may be fixedly disposed on the track. The second device 104 may be an RFID chip capable of a close range communication connection with the first device 103, and the second device 104 may be disposed between the two terrestrial APs 102. For example, the second device 104 may be disposed at a location intermediate to the two terrestrial APs 102. When the subway moves, the mobile AP101 moves along with the movement, and the mobile AP101 can switch from one ground AP102 to connect with another ground AP102, so as to ensure the communication quality of the subway in the operation process. The server 105 may be a remote server. The server 105 may be a server provided by a subway management system. Mobile AP101 may communicate with first device 103 and server 105.

The technical solutions provided by the embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, the application scenario shown in fig. 1 is taken as an example.

Referring to fig. 2, a method for switching a wireless access point is provided in an embodiment of the present invention, and a flow of the method is described as follows.

Step 201: mobile AP101 receives a first message from first device 103.

Wherein the first message carries a first identifier of the second device 104, and the first identifier may be regarded as identity information of the second device 104. The first identity of different second devices 104 is also different. For example, the first identifier may be a (media access control, MAC) address.

In the embodiment of the present invention, the first identifier is obtained by the first device 103 from the second device 104 through the short-range communication. For example, the first device 103 is an RFID reader, the second device 104 is an RFID chip, and the first device 103 and the second device 104 can communicate in a near field communication manner. As shown in fig. 1, the first device 103 is disposed on a subway and the plurality of second devices 104 are disposed on a track. The first device 103 moves along with the movement of the subway, and during the movement, the first device 103 can transmit a radio frequency signal of a specific frequency to an area of a certain size through the transmitting antenna, wherein the size of the area depends on the transmitting power of the first device 103. The subway provided with the first device 103 gradually approaches the second device 104 in the driving process, when the distance between the first device 103 and the second device 104 meets the requirement of the near field communication mode between the first device 103 and the second device 104 for the distance, the second device 104 can receive the radio frequency signal sent by the first device 103 through the electromagnetic induction coil to generate induction current, so that power is supplied to the second device, and the first device 103 and the second device 104 establish near field communication connection.

The first device 103 and the second device 104 establish a near field communication connection, and the second device 104 can actively send the first identifier to the first device 103 through the near field communication connection without sending a request by the first device 103, thereby reducing the interaction process between the devices. The first device 103 obtains the first identity and may inform the mobile AP101 of the first identity. For example, the mobile AP101 may also be disposed on a subway, and the first device 103 may send a first message to the mobile AP101, where the first message may carry the first identifier, so that the first device 103 informs the mobile AP101 of the first identifier. The mobile AP101, receiving the first identity, may cache the mobile AP locally.

When the first device 103 and the second device 104 satisfy the requirement of the proximity communication method for the distance, the second device 104 transmits the first identifier to the first device 103, so that the first device 103 can determine the location of the second device 104 as the location of the first device 103 upon receiving the first identifier. And the first device 103 and the mobile AP101 are both disposed on the subway, so that the mobile AP101 receives the first identifier, and may also determine the location of the second device 104 as the location of the mobile AP 101.

In some embodiments, before the mobile AP101 receives the first identifier, the operating mode of the mobile AP101 may be switched to a non-root bridge mode, i.e., an operating mode in which information from external devices may be received. For example, the mobile AP101 may receive a first instruction sent from a device in which the AP management system is installed, where the first instruction may be an instruction for instructing the mobile AP to switch the operating mode to the non-root bridge mode, so that when the first instruction is received, the mobile AP may switch the operating mode to the non-root bridge mode to receive the first identifier from the first device 103.

In the embodiment of the present invention, since the location of the second device 104 can be determined as the location of the mobile AP101, the terrestrial AP102 within a first preset range from the second device 104 can be considered as an AP closer to the mobile AP101, for example, the first preset range may be 500 meters. However, among the plurality of terrestrial APs 102 within the first predetermined range from the second device 104, there may be a stronger signal strength of the terrestrial AP102 and a weaker signal strength of the terrestrial AP 102. When the mobile AP101 selects an AP from the plurality of terrestrial APs 102 for connection, an AP that responds preferentially may be connected, and the AP that responds preferentially may not be closer to the mobile AP101 and may have a stronger signal strength. Accordingly, in an embodiment of the present invention, the second identifiers and corresponding signal strengths of the plurality of terrestrial APs 102 within a first preset range from the second device 104 may be sent to the server 105. Through a screening rule preset in the server 105, the mobile AP101 is connected to the ground AP102 which is as close as possible to itself and has a strong signal strength. That is, the mobile AP101 is connected to the AP adapted to the plurality of ground APs 102 in the first preset range as much as possible, thereby ensuring better communication quality.

Step 2011: the mobile AP101 listens to messages broadcast by the terrestrial AP 102.

A plurality of terrestrial APs 102 within a first predetermined range from the second device 104 may periodically broadcast messages. The message may include a second identification of the terrestrial AP102 and a signal strength. The second identifier may be information of a unique identifier of the ground AP102, for example, the second identifier may be a MAC address of the ground AP102, or may also be a Basic Service Set (BSS) Identifier (ID).

Since the plurality of terrestrial APs 102 are located within the first preset range of the second device 104, that is, are closer to the second device 104, when the first device 103 and the second device 104 meet the requirement of the short-range communication method for distance, the distance between the mobile AP101 and the terrestrial AP102 is also closer. When the first device 103 sends the acquired first identifier of the second device 104 to the mobile AP101, the mobile AP101 may start listening to a message broadcast by at least one terrestrial AP within a first preset range around the second device 104, where the message corresponds to the first identifier.

In some embodiments, the mobile AP101 may be disposed at the top of a subway car, the first device 103 may be disposed at the bottom of the subway car, the plurality of ground APs 102 are disposed inside a subway tunnel, and the mobile AP101, the first device 103, and the second device 104 are in the same line and perpendicular to the ground. Thus, when the first device 103 receives the first identifier of the second device 104, the message broadcasted by the ground AP102 intercepted by the mobile AP101 is a message broadcasted by the ground AP102 within a first preset range from the second device 104, and the message is relatively accurate and can truly reflect the signal strength of the ground AP102 at the current location. Further, the second device 104 may be located at a middle position between the two ground APs 102, so that after the first device 103 receives the first identifier, the ground AP102 intercepted by the mobile AP101 is the ground AP102 closer to the mobile AP 101.

Step 2012: the mobile AP101 generates a first packet according to the first identifier, the second identifier and the corresponding signal strength.

After the mobile AP101 senses a second identifier and a corresponding signal strength of at least one terrestrial AP102 within a first preset range from the second device 104, a first message may be generated according to the first identifier, the second identifier and the corresponding signal strength. The first message may indicate correspondence between the first identifier and the second identifier and the signal strength of the at least one terrestrial AP102, respectively.

Step 202: mobile AP101 sends a first message to server 105.

Mobile AP101 generates a first message that may be sent to server 105. For example, the first message may be a Transmission Control Protocol (TCP) message, a hyperText transfer protocol (HTTP) message, or an extensible markup language (XML) message.

Step 2021: the server 105 determines the first target AP according to the first packet.

In some possible cases, the unreasonable ground AP102 exists in the at least one ground AP102 that the mobile AP101 senses, that is, the unreasonable ground AP102 exists in the at least one ground AP102 corresponding to the first message. For example, in a closed environment inside a tunnel, a message broadcasted by at least one terrestrial AP102 may be repeatedly reflected, and the at least one terrestrial AP102 may include a terrestrial AP102 farther away from the current second device 104, that is, a terrestrial AP102 located near a first predetermined range critical position of the current second device 104. Alternatively, the terrestrial AP102 of the at least one AP102 may be located behind the second device 104, i.e. opposite to the moving direction of the mobile AP101, and the terrestrial AP102 opposite to the moving direction of the mobile AP101 may be out of the coverage of the mobile AP101 at the next moment. Or, due to the close distance between the subway running rails, the at least one ground AP102 may include a ground AP102 on the other side of the side rail opposite to the current running rail.

For this purpose, after receiving the first message, the server 105 may delete a part of the at least one terrestrial AP102 in the terrestrial AP102 corresponding to the first message according to a preset rule. Here, some of the terrestrial APs 102 may be unreasonable terrestrial APs 102. Here, the unreasonable ground AP102 refers to a ground AP102 farther from the mobile AP101 within a first preset range, which is also referred to as a far-end ground AP102, may refer to a ground AP102 in an opposite orbit to the mobile AP101, which is also referred to as a ground AP102 in an opposite orbit, and may refer to a ground AP102 in an opposite direction to the mobile AP, which is also referred to as an opposite ground AP 102. Therefore, at least one target AP which is close to the mobile AP101 and is positioned on the same track and in the same direction as the mobile AP101 is reserved, and the communication quality is guaranteed as much as possible.

In some embodiments, the preset rules may include one or more combinations of the following:

in a first preset rule, the server 105 screens out the ground APs 102 in the first message, which are more than a second range from the second device 104, where the second preset range is less than the first preset range. Since the closed environment inside the tunnel may reflect the message sent by the ground AP102, the message heard by the mobile AP101 is a message broadcast by at least one ground AP102 adjacent to the mobile AP101, and may also come from a ground AP102 located farther away within the first predetermined range. Specifically, the position of the second device 104 may be used as an origin, and the second preset range is used as a radius, and the ground AP102, which is greater than the second preset range from the second device 104, in the at least one ground AP102 corresponding to the first message is screened out. Therefore, the remote ground AP102 can be screened out, so that the mobile AP101 is prevented from establishing connection with the remote ground AP102, and the communication quality is ensured. It should be noted that the first length may be set in advance according to practical experience, for example, the first length is 100 meters.

In a second predetermined rule, the server 105 screens the ground APs 102 in the first message that are farther and farther from the mobile AP101, that is, screens the ground APs 102 located in the opposite direction to the mobile AP 101. Specifically, the forward direction of the subway may be defined as the forward direction, and although there are multiple adjacent terrestrial AP102 broadcast messages in both the forward direction and the reverse direction of the second device 104, since the subway is in a high-speed running state, at the next moment, the coverage area of the terrestrial AP102 in the reverse direction is not already covered by the mobile AP 101. Therefore, to ensure the communication quality, the server 105 may screen out a plurality of terrestrial APs 102 in the first message, which are located in the opposite direction.

In a third preset rule, the server 105 screens out the ground AP102 in the reverse orbit in the first message. Specifically, the reverse track here refers to a second track adjacent to the first track where the mobile AP101 is located. Due to the close distance between adjacent running tracks of the subway, for example, the mobile AP101 on the first track may sense the message broadcast by the ground AP102 on the second track side. To eliminate the possibility of the mobile AP101 establishing a connection with a terrestrial AP102 in a reverse orbit, the server 105 may exclude the terrestrial AP102 in the reverse orbit from the first message.

And according to a fourth preset rule, the server screens the ground AP102 with the signal strength lower than the first threshold value in the first message. Wherein the first threshold may be one possible value set according to historical data. Among the plurality of terrestrial APs 102, there may be a terrestrial AP102 having a stronger signal strength and a terrestrial AP102 having a weaker signal strength. To ensure the communication quality, the server 105 may screen the terrestrial AP102 in the first message whose signal strength is lower than the first threshold value, so as to ensure the communication quality. Therefore, the user does not feel obvious pause when watching videos on line or does not have obvious delay when sending messages by using chat application software through the mobile terminal, and the user experience is improved.

After a part of the at least one terrestrial AP102 is screened out according to the preset rule, the remaining at least one terrestrial AP102 may be considered as an AP which is closer to the current mobile AP101 and has a stronger signal strength. Since the mobile AP101 may establish a connection with a certain terrestrial AP102 of the remaining at least one terrestrial AP102, the remaining at least one terrestrial AP102 may be considered as at least one target AP to which the mobile AP101 is to connect.

In some embodiments, it is considered that when the mobile AP101 listens to the message of the at least one terrestrial AP102, it does not listen to the message broadcast by the AP, which is closer to the mobile AP101 and has a stronger actual signal strength, of the at least one terrestrial AP 102. For example, the current time monitored by the mobile AP101 is just in the time gap of the AP broadcast message with stronger actual signal strength, so the second identifier and the signal strength of the AP with stronger actual signal strength do not exist in the first message sent by the mobile AP101 to the server 105. In this way, the server 105 does not have the second identifier and the signal strength of the AP with stronger actual signal strength in at least one target AP obtained after screening according to the preset rule. Alternatively, in some embodiments, the signal strength may fluctuate over time to account for the terrestrial AP102, which may result in an AP that was previously actually stronger in signal strength may be weaker in signal strength at some point, and may return to normal in signal strength thereafter. If this is the case, the AP with the stronger actual signal strength may be screened out by the server 105 according to the fourth preset rule.

In view of this, in the embodiment of the present invention, the server 105 may combine the current first message and information in the plurality of historical first messages, and ensure that at least one target AP obtained after the screening by the server 105 includes an AP that is actually more suitable. Specifically, the mobile AP101 may send a first packet to the server 105 multiple times, and the server 105 receives the first packet sent by the mobile AP101 again, analyzes the first packet, and obtains a matching relationship between a first identifier in the first packet and multiple second identifiers and corresponding signal strengths. The server 105 obtains the first identifier and the plurality of second identifiers, and may compare the first identifier with the first message received many times before, if the first message received many times before includes the second identifier of the AP which is closer to the current mobile AP101 and has stronger actual signal strength, even if the first message received this time does not include the second identifier of the AP having stronger actual signal strength, the server 105 may regard the ground AP102 corresponding to the second identifier as the ground AP102 which is closer to the mobile AP101 and has stronger signal strength. The server 105 obtains the first identifier and the plurality of second identifiers, and may query, from the first message received for multiple times, historical signal strengths corresponding to the plurality of second identifiers, and for each second identifier, accumulate the signal strength at the current time and the historical signal strength and find an average value as the signal strength of the ground AP102, so as to avoid screening out the ground AP102 with a strong actual signal strength according to a preset rule, that is, to ensure that at least one target AP obtained after being screened by the server 105 includes an AP that is actually adapted.

After determining the at least one target AP, the server may select an AP that is closer to the current mobile AP101 and has a stronger signal strength, that is, the first target AP, from the at least one target AP.

Step 203: the mobile AP101 receives the second message from the server 105.

Wherein the second message includes a second identifier of the first target AP, and the first target AP is an AP with the strongest signal strength among the at least one terrestrial AP 102.

After determining the first target AP from the at least one target AP, the server 105 may notify the other device of the first target AP, for example, the other device may be a device that installs an AP management system. In this embodiment of the present invention, the server 105 may send a second message to the other device, where the second message may carry the second identifier of the first target AP. The second identifier of the first target AP may be a MAC address of the first target AP, or may also be an Identity Document (ID) of a Basic Service Set (BSS). After receiving the second message, the other device sends the second message to the mobile AP 101. The mobile AP101 receives the second message, obtains the identifier of the first target AP from the second message, and determines the first target AP.

Step 204: the mobile AP101 establishes a connection with the first target AP.

After determining the first target AP, the mobile AP101 may establish a connection with the first target AP. Specifically, the mobile AP101 may send a Probe Request (Probe Request) message to the first target AP to Request to join the network where the first target AP is located. The first target AP receives the Probe Request message, and may send a Probe Response (Probe Response) message for responding to the Probe Request frame to the mobile AP101, that is, complete the scanning phase of establishing the connection; thereafter, mobile AP101 may send an Authentication Request (Authentication Request) message to the first target AP, which may be used to Request Authentication from the first target AP. The first target AP receives the Authentication request message and sends an Authentication Response (Authentication Response) message to the mobile AP101, thereby completing the Authentication phase of establishing a connection; thereafter, the mobile AP101 may transmit an Association Request (Association Request) message to the first target AP, the Association Request message requesting Association with the first target AP. The first target AP receives the Association request message, and may send an Association Response (Association Response) message to the mobile AP101, that is, complete the Association phase of establishing the connection. The mobile AP101 receives the association response message and establishes a connection with the first target AP.

If the mobile AP101 fails to establish a connection with the first target AP, in order to meet the requirement of fast roaming, for example, the handover procedure of the mobile AP101 is completed within 50ms, the mobile AP101 may acquire a terrestrial AP102 from the server 105 again as the second target AP to establish a connection.

In the embodiment of the present invention, the mobile AP101 may send a first prompting message to the server 105, where the first prompting message is used to inform the server 105 that the connection between the mobile AP101 and the first target AP fails at the current location of the second device 104. After receiving the first prompt message, the server 105 selects one AP from the at least one target AP obtained through the screening in step 2021 as a second target AP, and notifies the other devices of the second target AP. For example, the other device may be a device that installs the AP management system. The distance between the second target AP and the mobile AP101 may be considered to be closest to the mobile AP except the first target AP, and the signal strength of the second target AP may be considered to be strongest except the first target AP, that is, the second target AP may be considered to be an AP better adapted to the mobile AP except the first target AP.

Specifically, the server 105 may send a third message to the other device, where the third message may carry the second identifier of the second target AP. The second identifier of the second target AP may be a MAC address of the second target AP, or may also be an Identity Document (ID) of a Basic Service Set (BSS). After receiving the third message, the other devices send the third message to the mobile AP 101. The mobile AP101 receives the third message, acquires the second identifier of the second target AP from the third message, and further determines the second target AP. The process of establishing the connection between the mobile AP and the second target AP may refer to step 204, and is not described herein again.

In the long-term operation process of the subway, for example, one month, the mobile AP may pass through the same second device 104 for multiple times, and repeat all the steps, and finally, the mobile AP may form a relatively stable connection relationship at each second device 104, that is, once the mobile AP travels to each second device 104, the mobile AP may fixedly establish a connection with one of the ground APs 102. We can refer to this stable connection relationship optimized over time as a historical connection relationship, and the terrestrial AP104 that is stably connected with the mobile AP at each second device 104 as a historical target AP. In this embodiment of the present invention, if the mobile AP101 does not establish a connection with the historical target AP at the location while passing through a certain second device 104, the mobile AP101 may send a second prompt message to the server 105, where the second prompt message is used to inform the server 105 that the first target AP currently establishing a connection with the mobile AP101 is different from the historical target AP. If the number of times that the server 105 receives the second prompting message exceeds a first threshold value, for example, the first threshold value is 5 times, within a certain time period, for example, 1 day, the server 105 may determine that the historical target AP at the current location of the second device 104 has failed, and output alarm information. The alarm information can include the position information of the failed historical target AP, so that the maintenance can be conveniently carried out by related personnel.

The following describes the apparatus provided by the embodiment of the present invention with reference to the drawings.

Referring to fig. 3, based on the same inventive concept, the present invention provides an AP, including: a receiving module 301, a sending module 302 and a connecting module 303.

A receiving module 301, configured to receive a first message from a first device 103, where the first message carries a first identifier of the first device 103, a distance between an AP and the first device 103 is smaller than a first threshold, and the first identifier is obtained by the first device 103 from at least one second device 104 in a near field communication manner during a moving process;

a sending module 302, configured to send a first message to the server 105, where the first message is used to indicate a second identifier of at least one ground AP102 corresponding to the first identifier and a signal strength of each ground AP102, and the at least one ground AP102 is an AP whose distance from the second device 104 is smaller than a second threshold;

a receiving module 301, further configured to receive a first message from the server 105, where the first message includes a second identifier of a first target AP, and the first target AP is an AP with the strongest signal strength among the at least one ground AP 102;

a connection module 303, configured to establish a connection with the first target AP.

Optionally, the system further comprises a switching module;

wherein, the receiving module 301 is further configured to: before the AP receives the first message from the first device 103, receiving a first instruction, where the first instruction is used to instruct the AP to switch the operating mode to the non-root bridge mode; the non-root bridge mode is used for representing that the AP can receive data output by external equipment;

the switching module is configured to switch the operating mode of the AP to the non-root bridge mode when it is determined that the receiving module 301 receives the first instruction.

Optionally, the sending module 302 is configured to send a first prompt message to the server 105 when the AP fails to connect to the first target AP;

a receiving module 301, configured to receive a third message from the server 105, where the third message includes a second identifier of a second target AP, where a signal strength of the second target AP is strongest in at least one terrestrial AP102 except for the first target AP;

and the connection module is also used for connecting with a second target AP.

Optionally, the determining module is further configured to determine that the first target AP is different from the historical target AP corresponding to the second device 104;

the sending module 302 is further configured to send a second prompt message to the server 105, where the second prompt message is used to prompt the history that the target AP has failed.

Referring to fig. 4, based on the same inventive concept, the present invention provides a server, including: a receiving module 401, a determining module 402 and a sending module 403.

A receiving module 401, configured to receive a first message from the mobile AP101, where the first message is used to indicate a second identifier of at least one ground AP102 corresponding to the first identifier of the second device 104 and a signal strength of each ground AP102, where the first identifier is an identifier obtained by the first device 103 from the second device 104 in a short-distance communication manner during a moving process and sent to the mobile AP101, and the at least one ground AP102 is an AP whose distance from the second device 104 is smaller than a second threshold;

a determining module 402, configured to determine a first target AP from the at least one ground AP102 according to the first message, where the first target AP is an AP with the strongest signal strength among the at least one ground AP 102;

a sending module 403, configured to send a first message to the mobile AP101, where the first message includes a second identifier of the first target AP101, so that the mobile AP101 establishes a connection with the first target AP.

Optionally, the determining module 402 is specifically configured to:

screening at least one ground AP102 according to a preset rule to obtain at least one target AP;

a first target AP is determined from the at least one target AP.

Optionally, the determining module 402 is further configured to:

and screening at least one ground AP102 according to the first message and a plurality of historical first messages to obtain at least one target AP.

Optionally, the receiving module 401 is further configured to receive second prompt information from the mobile AP101, where the second prompt information is used to prompt the server 105 that the historical target AP has failed;

the sending module 403 is further configured to output an alarm message for prompting the maintenance staff to history the target AP failure under the control of the determining module 402 determining that the number of times of the received second prompt message exceeds the first threshold.

Referring to fig. 5, based on the same inventive concept, an embodiment of the present invention provides a wireless access point AP, including: at least one processor 501, where the processor 501 is configured to execute a computer program stored in a memory, to implement the steps of the wireless access point handover method as shown in fig. 2 according to an embodiment of the present invention.

Optionally, the processor 501 may be specifically a central processing unit, an Application Specific Integrated Circuit (ASIC), and may be one or more integrated circuits for controlling program execution.

Optionally, the wireless access point further comprises a memory 502 coupled to the at least one processor 501, and the memory 502 may include a Read Only Memory (ROM), a Random Access Memory (RAM), and a disk memory. The memory 502 is used for storing data required by the processors 501 during operation, that is, storing instructions executable by at least one of the processors 501, and the at least one of the processors 501 executes the instructions stored in the memory 502 to perform the method shown in fig. 2. The number of the memories 502 is one or more. The memory 502 is also shown in fig. 5, but it should be understood that the memory 502 is not an optional functional block, and is therefore shown in fig. 5 by a dotted line.

The physical devices corresponding to the receiving module 301, the sending module 302 and the connecting module 303 may be the processor 501. The wireless access point may be configured to perform the method provided by the embodiment shown in fig. 2. Therefore, regarding the functions that can be realized by each functional module in the device, reference may be made to the corresponding description in the embodiment shown in fig. 2, which is not repeated herein.

Referring to fig. 6, based on the same inventive concept, an embodiment of the present invention provides a server, including: at least one processor 601, where the processor 601 is configured to execute a computer program stored in a memory, to implement the steps of the wireless access point handover method as shown in fig. 2 according to the embodiment of the present invention.

Alternatively, the processor 601 may be specifically a central processing unit, a specific ASIC, and may be one or more integrated circuits for controlling the execution of the program.

Optionally, the server further comprises a memory 602 connected to the at least one processor 601, the memory 602 may comprise ROM, RAM and disk memory. The memory 602 is used for storing data required by the processor 601 during operation, that is, storing instructions executable by the at least one processor 601, and the at least one processor 601 executes the instructions stored in the memory 602 to perform the method shown in fig. 2. The number of the memories 602 is one or more. The memory 602 is also shown in fig. 6, but it should be understood that the memory 602 is not an optional functional module, and is therefore shown in fig. 6 by a dotted line.

The physical devices corresponding to the receiving module 401, the determining module 402, and the sending module 403 may be the processor 601. The server may be used to perform the method provided by the embodiment shown in fig. 2. Therefore, regarding the functions that can be realized by each functional module in the device, reference may be made to the corresponding description in the embodiment shown in fig. 2, and details are not repeated here.

With continuing reference to fig. 1, based on the same inventive concept, an embodiment of the present invention provides a communication system, where the communication system includes an AP as in the embodiment of fig. 3 and a server as in the embodiment of fig. 4, and a first device 103, a second device 104, and at least one terrestrial AP102, where a distance between the AP as in the embodiment of fig. 3 and the first device 103 is smaller than a first threshold, the first device 103 communicates with the second device 104 through a short-range communication method, and the at least one terrestrial AP102 is an AP whose distance between the AP and the second device 104 is smaller than a second threshold.

Embodiments of the present invention also provide a computer storage medium, where the computer storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer is caused to execute the method as described in fig. 2.

It is obvious to those skilled in the art that, for convenience and simplicity of description, the above division of each functional module is only used for illustration, and in practical applications, the above function distribution may be performed by different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to perform all or part of the above described functions. For the specific working processes of the system, the apparatus and the unit described above, reference may be made to the corresponding processes in the foregoing method embodiments, and details are not described here again.

Claims

1. A method for switching an AP (access point), the method comprising:

the mobile AP sends a first message to a server, wherein the first message is used for indicating a second identifier of at least one ground AP corresponding to the first identifier and the signal strength of each ground AP, and the distance between the at least one ground AP and the second equipment is smaller than a second threshold value;

the mobile AP establishes connection with the first target AP;

the first equipment is arranged on a subway, and the second equipment is arranged on the ground.

2. The method of claim 1, wherein prior to the mobile AP receiving the first message from the first device, further comprising:

3. The method of claim 1 or 2, wherein the method further comprises:

the mobile AP connects with the second target AP.

4. The method of claim 1 or 2, wherein the method further comprises:

5. A method for switching an AP (access point), the method comprising:

the server sends a first message to the mobile AP, wherein the first message comprises a second identifier of a first target AP, so that the mobile AP can establish connection with the first target AP;

6. A wireless access point, AP, comprising:

a connection module, configured to establish a connection with the first target AP;

7. A server, characterized in that the server comprises:

a receiving module, configured to receive a first message from a mobile AP, where the first message is used to indicate a second identifier of at least one ground AP corresponding to a first identifier of a second device and a signal strength of each ground AP, where the first identifier is an identifier obtained by a first device from the at least one second device in a short-distance communication manner during a moving process and sent to the mobile AP, and the at least one ground AP is an AP whose distance from the first device to the second device is smaller than a second threshold;

a determining module, configured to determine a first target AP from the at least one ground AP according to the first packet, where the first target AP is an AP with the strongest signal strength among the at least one ground AP;

a sending module, configured to send a first message to the mobile AP, where the first message includes a second identifier of a first target AP, so that the mobile AP establishes a connection with the first target AP;

8. A wireless access point, AP, comprising at least one processor and memory coupled to the at least one processor, the at least one processor being configured to implement the steps of the method of any one of claims 1-4 or 5 when executing the computer program stored in the memory.

9. A communication system comprising the AP of claim 6 and the server of claim 7, and a first device, a second device, at least one terrestrial AP, wherein a distance between the AP and the first device is less than a first threshold, the first device communicates with the second device by means of close-range communication, and the at least one terrestrial AP is an AP whose distance between the AP and the second device is less than a second threshold.

10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method according to any one of claims 1-4 or 5.