CN103281720B

CN103281720B - The hot standby changing method of wireless controller and device, wireless controller, connecting system

Info

Publication number: CN103281720B
Application number: CN201310206450.1A
Authority: CN
Inventors: 林丹宁
Original assignee: Fujian Star Net Communication Co Ltd
Current assignee: Ruijie Networks Co Ltd
Priority date: 2013-05-29
Filing date: 2013-05-29
Publication date: 2016-03-30
Anticipated expiration: 2033-05-29
Also published as: CN103281720A

Abstract

The invention discloses the hot standby changing method of a kind of AC and device, wireless controller, wireless access system, wherein, main AC and standby AC is after first connection is set up, consult to generate and preserve and connect sequence number, and be handed down at main AC in the switching message of AP and carry this connection sequence number, AP preserves the connection sequence number received successively, after the hot standby switching of AC, the connection sequence number of self preserving is increased fixed numbers by the main AC after switching, and the connection sequence number after this increase is carried at switch in message and sends to AP, and with switch after standby AC rebuild and communicate after, consult with standby AC and determine a consistent connection sequence number, and preserve this connection sequence number, AP according to the connection sequence number of self preserving and receive several switch the switching message at the maximum connection sequence number place of numerical value in the connection sequence number of message, set up the communication between main AC, correctly effectively can set up with correct main AC and communicate, shorten the time of AP cutout.

Description

Wireless controller hot standby switching method and device, wireless controller and access system

Technical Field

The present invention relates to a network communication system, and in particular, to a method and an apparatus for hot standby switching of a wireless controller, and a wireless access system.

Background

In the deployment of the wireless local area network, there are two current deployment modes: a thin wireless Access Point (AP) mode and a fat AP mode. Among them, the thin AP mode gradually becomes the mainstream deployment mode. In the thin AP mode deployment, there are two types of wireless devices: a radio controller (AC) and an AP; the AP needs to establish connection with the AC, then the user performs unified configuration on the AC, and the AC sends the relevant configuration to the AP. The AC and the AP cooperate to provide the service of the wireless local area network for the user. The specifications for cooperation between the AC and the AP are defined in RFC5415, which is a wireless access point control and provisioning protocol (CAPWAP) protocol.

Provision is made in the CAPWAP protocol for: after the AC establishes CAPWAP connection with the AP, a CAPWAP communication tunnel is established between the AC and each AP, and each message sent to the AP by the AC must pass through the CAPWAP communication tunnel; each message sent by the AP to the AC must also pass through the CAPWAP communication tunnel. The CAPWAP communication tunnel is a point-to-point tunnel and a unicast tunnel. As shown in fig. 1.

The hot backup function of the AC is to provide a CAPWAP tunnel switching capability of millisecond level between the AC and the AP when the AC is unreachable (for example, the AC fails), so as to ensure that the associated user service is uninterrupted to the maximum extent. As shown in fig. 2, the processing procedure of CAPWAP tunnel switching includes:

step one, two ACs determine a main AC and a standby AC through negotiation, and keep-alive is carried out between the ACs through a keep-alive mechanism;

step two, the AP establishes a main CAPWAP tunnel with the main AC and establishes a standby CAPWAP tunnel with the standby AC;

step three, the user uses the wireless client to associate to the AP;

step four, the user carries out network communication with the outside through a main CAPWAP tunnel of the AP and the AC;

step five, when the main AC fails, the standby AC detects the overtime of the keep-alive and immediately informs the AP;

step six, activating a standby CAPWAP tunnel between the standby AC and the AP; the standby AC becomes the main AC;

seventhly, the service of the user is recovered to be normal after the CAPWAP tunnel is activated;

step eight, when the original main AC returns to normal, reestablishing a hot standby relation with the new main AC, and changing the original main AC into a standby AC; AP establishes a CAPWAP tunnel with the AP; the service of the user is not interrupted.

In this process, if the network between the primary AC and the standby AC is temporarily unreachable, the standby AC detects that the hot-standby connection is disconnected to trigger AC hot-standby switching and convert the hot-standby connection into the primary AC, and the switched primary AC issues a switching CAPWAP tunnel message (CW 1 for short) to the AP. The main/standby AC reestablishes communication in a short time, but if the hot standby connection is disconnected again, that is, a phenomenon of 'flash' occurs, a second AC hot standby switching is triggered, the standby AC after the first switching is converted into the main AC, and the main AC after the second switching also sends a switching message (referred to as CW2 for short) to the AP. At this point the AP will receive two handoff messages. If the message of CW2 comes first and the message of CW1 comes later due to network congestion or CAPWAP retransmission, the AP switches to the primary AC after the second switch first and then switches to the standby AC after the second switch, so that the primary AC selected by the AP is inconsistent with the actual primary AC, thereby making the network unavailable and causing user traffic interruption.

In the prior art, the main solutions are as follows:

the method comprises the following steps: directly without treatment. This is because, in the case where an AC hot standby switch is caused by a failure of the main AC, if an AP is erroneously connected to the AC, the AC is already unavailable and the switch message is not issued, so there is no need for processing.

The method 2 comprises the following steps: the direct evasion is that if the AC hot standby switching is caused by the link failure between the main AC and the standby AC, if the AP is connected to the switched standby AC in error, the standby AC disconnects the communication between the AP and the standby AC, and the AP is connected to the main AC again.

The method 3 comprises the following steps: the master AC for each AC hot-standby switch records a timestamp when sending the switch message. And when the AP receives the message, comparing the time stamps, and not processing the message with the older time stamp.

However, all of the above three methods have certain drawbacks. Method 1 fails to address this problem. Method 2 merely circumvents this problem and cannot solve it. The method 3 requires that the timestamps of the two ACs are consistent, and the timestamps between the two ACs cannot be completely consistent in a real environment. Thus, the AP's off time is extended before the AP reconnects to the correct AC.

Therefore, in the wireless access system of the existing thin AP architecture, when the AC hot standby is switched, the problem that the AP cannot be correctly connected to the main AC and the disconnection time of the AP is prolonged after the switching message arrives at the AP out of order cannot be effectively handled.

Disclosure of Invention

In view of this, embodiments of the present invention provide an AC hot standby switching method and apparatus, a wireless controller, and a wireless access system, so as to solve the problem that when an AC hot standby is switched in an existing thin AP architecture, the AP cannot be correctly connected to a main AC and the disconnection time of the AP is prolonged because a switching message arrives at the AP out of order in the existing thin AP architecture wireless access system.

The technical scheme of the embodiment of the invention is as follows:

a wireless controller AC hot standby switching method comprises the following steps: the AC judges whether the AC is a main AC after connection is established for the first time or whether the AC is a main AC after AC hot standby switching; under the condition that the AC judges that the AC is the main AC after the connection is established for the first time, the main AC and the standby AC negotiate to determine a connection serial number and store the connection serial number; the main AC carries the determined connection sequence number in a switching message and sends the switching message to an Access Point (AP); wherein, the connection serial number is saved by the AP; under the condition that the AC judges and confirms that the AC is the main AC after the AC hot standby switching, the main AC after the switching increases the connection serial number stored by the AC by a fixed value, and stores the increased connection serial number; the main AC after switching carries the increased connection serial number in a switching message and sends the switching message to the AP, wherein the connection serial number is the switching message in which the AP sequentially stores the received connection serial numbers and establishes communication with the main AC for reference according to the connection serial number stored by the AP and the connection serial number with the largest value in the connection serial numbers of the plurality of received switching messages; and after the switched main AC and the switched standby AC reestablish communication, sending the stored connection serial number to the standby AC, negotiating with the standby AC, determining a consistent connection serial number, and storing the connection serial number.

A wireless controller AC hot standby switching method comprises the following steps: the AC judges whether the AC is a standby AC after connection is established for the first time or whether the AC is a standby AC after AC hot standby switching; under the condition that the AC judges and confirms that the AC is the standby AC after the connection is established for the first time, the standby AC negotiates with the main AC to determine a connection serial number, and the connection serial number is stored; wherein, the connection serial number is sent to the AP by the main AC and stored by the AP; under the condition that the AC judges that the AC is the standby AC after the AC hot standby switching, the switched standby AC receives a connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiates with the main AC and determines a consistent connection serial number, and stores the connection serial number; the received connection serial number from the main AC is sent to the AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for establishing communication with the main AC according to the switching message where the connection serial number with the largest value in the connection serial numbers of the plurality of switching messages stored by the AP is located.

A wireless controller AC hot standby switching device, comprising: the device comprises a judging module, a determining module, a storing module, a sending module, a connection sequence number increasing module and a negotiation module; the judging module is used for judging whether the AC to which the device belongs is a main AC after the first connection is established or a main AC after the hot standby switching of the AC; the determining module is configured to negotiate with the standby AC to determine a connection sequence number when the determining module determines that the AC to which the device belongs is the main AC after the first connection is established; the storage module is used for storing the connection serial number determined by the determination module; saving the connection serial number increased by the connection serial number increasing module; storing the connection serial number determined by the negotiation module; the sending module is configured to send the connection sequence number determined by the determining module to the AP in a handover message, where the connection sequence number is stored by the AP; the connection serial number increased by the connection serial number increasing module is carried in a switching message and sent to the AP, the connection serial number is the switching message in which the AP sequentially stores the received connection serial numbers, and the communication with the main AC is established for reference according to the connection serial number stored by the AP and the switching message in which the connection serial number with the largest value in the connection serial numbers of the received switching messages is located; the connection sequence number increasing module is used for increasing the connection sequence number stored by the storage module by a fixed value under the condition that the judging module judges that the AC to which the device belongs is the main AC after the AC hot standby switching; and the negotiation module is used for sending the connection serial number stored by the storage module to the standby AC after the communication between the switched main AC and the switched standby AC is reestablished under the condition that the judgment module judges the main AC after the AC hot standby switching, negotiating with the standby AC and determining a consistent connection serial number.

A wireless controller AC hot standby switching method comprises a judging module, a determining module, a negotiation module and a storage module; the judging module is used for judging whether the AC to which the device belongs is the standby AC after the connection is established for the first time or whether the AC is the standby AC after the hot standby switching of the AC; the determining module is configured to negotiate with a main AC to determine a connection serial number when the determining module determines that the AC to which the device belongs is the standby AC after connection is established for the first time, where the connection serial number is sent from the main AC to an access point AP and is stored by the AP; the negotiation module is configured to, when the judgment module judges that the AC to which the device belongs is the standby AC after the AC hot standby switching, receive a connection serial number from the main AC after the switched standby AC reestablishes communication with the switched main AC, negotiate with the main AC, and determine a consistent connection serial number; the method comprises the steps that a received connection serial number from a main AC is sent to an AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for communication between the AP and the main AC according to the connection serial number stored by the AP and a switching message where the connection serial number with the largest value in the connection serial numbers of a plurality of received switching messages is located; the storage module is further configured to store the connection sequence number determined by the determination module, and store the connection sequence number determined by the negotiation module.

A wireless controller comprising a wireless controller AC hot standby switching arrangement as described above, or comprising an AC hot standby switching arrangement as described above.

A wireless access system, comprising: a main AC, a standby AC and an AP; the main AC is used for judging whether the main AC is the main AC after connection is established for the first time or whether the main AC is the main AC after AC hot standby switching; under the condition that the main AC after the connection is established for the first time is judged and confirmed, the main AC and the standby AC negotiate to determine a connection serial number and store the connection serial number; the main AC carries the determined connection sequence number in a switching message and sends the switching message to an Access Point (AP); under the condition that the main AC after the AC hot standby switching is judged and confirmed, the main AC after the switching increases the connection serial number stored by the main AC by a fixed value, and stores the increased connection serial number; and the main AC after switching carries the increased connection sequence number in the switching message and sends the switching message to the AP; after the switched main AC and the switched standby AC reestablish communication, sending a stored connection serial number to the standby AC, negotiating with the standby AC, determining a consistent connection serial number, and storing the connection serial number; the standby AC is used for judging whether the standby AC is the standby AC after connection is established for the first time or whether the standby AC is the standby AC after AC hot standby switching; under the condition that the standby AC which is connected for the first time is judged and confirmed, the standby AC and the main AC negotiate to determine a connection serial number and store the connection serial number; under the condition that the self is judged to be the standby AC after the hot standby switching of the AC, the switched standby AC receives the connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiates with the main AC and determines a consistent connection serial number, and stores the connection serial number; and the AP is used for sequentially storing the connection serial numbers in the received switching messages after the CAPWAP tunnels are respectively established with the main AC and the standby AC, and establishing communication with the main AC according to the stored connection serial numbers and the switching message in which the connection serial number with the largest value is located in the connection serial numbers of the received switching messages.

In the embodiment of the invention, after the primary AC and the standby AC are connected for the first time, a connection serial number is generated and stored through negotiation, the connection serial number is carried in a switching message sent to an AP by the primary AC, the AP stores the connection serial numbers received in sequence, after the AC hot standby switching, the main AC after the switching increases the connection serial number stored by the main AC by a fixed value, the increased connection serial number is carried in the switching message and sent to the AP, after the communication is reestablished with the standby AC after the switching, the main AC negotiates with the standby AC and determines a consistent connection serial number, the connection serial number is stored, the AP establishes the communication with the main AC according to the switching message in which the connection serial number with the largest value among the connection serial numbers of a plurality of switching messages stored by the AP and received is located, because the connection serial numbers between the main AC and the standby AC are consistent after the connection is established for the first time or the AC hot standby switching occurs, and the value of the connection serial number is increased at the main AC of each switching, so that the value of the connection serial number carried in the switching message by the main AC after switching is larger than that of the standby AC, namely the value of the connection serial number carried in the switching message by the main AC before switching, even if a plurality of times of AC hot standby switching occurs between the main AC and the standby AC in a short time, the main AC before and after switching sends a plurality of switching messages to the AP, and the plurality of switching messages arrive at the AP in disorder, the AP establishes communication with the main AC according to the switching message with the largest value of the connection serial number in the switching messages, can accurately and effectively establish communication with the correct main AC, shorten the disconnection time of the AP and avoid the problem that the AP is connected to the wrong AP, thereby solving the problems that in the wireless access system with the existing thin AP framework, when the AC hot standby switching cannot be effectively processed, the AP cannot be accurately connected to the main AC after the switching messages arrive at the AP in, Prolonging the current interruption time of the AP.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

Fig. 1 is a block diagram of a network architecture of a WLAN with a thin AP architecture;

FIG. 2 is a flowchart illustrating the operation of AC hot standby switching in the prior art;

fig. 3 is a system block diagram of a wireless access system according to an embodiment of the present invention;

fig. 4 is a flowchart of an AC hot standby switching method according to an embodiment of the present invention;

fig. 5 is another working flow chart of the AC hot standby switching method according to the embodiment of the present invention;

fig. 6 is a flowchart of an AP operation in AC hot standby switching according to an embodiment of the present invention;

fig. 7 is a block diagram of an AC hot standby switching device according to an embodiment of the present invention;

fig. 8 is another block diagram of an AC hot standby switching device according to an embodiment of the present invention;

fig. 9 is a flowchart of another operation of the AC hot standby switching method according to the embodiment of the present invention;

fig. 10 is a further flowchart of an AC hot standby switching method according to an embodiment of the present invention.

Detailed Description

The embodiments of the present invention will be described in conjunction with the accompanying drawings, and it should be understood that the embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

The embodiment of the invention provides a hot standby switching scheme of a wireless controller to solve the problem that when AC hot standby switching cannot be effectively processed in a wireless access system of the existing thin AP architecture, switching messages arrive at an AP out of order, the AP cannot be correctly connected to a main AC, and the cut-off time of the AP is prolonged.

In the technical scheme provided by the embodiment of the invention, after connection is established for the first time or AC hot standby switching is generated, the main/standby ACs negotiate or keep consistent connection serial numbers, the numerical value of the connection serial numbers is increased progressively for the main AC switched every time, so that the numerical value of the connection serial numbers carried in the switching messages by the main AC after switching is larger than that of the standby AC, namely the connection serial numbers carried in the switching messages by the main AC before switching, even if a plurality of times of AC hot standby switching is generated between the main AC and the standby AC in a short time, the main AC before and after switching sends a plurality of switching messages to the AP, the plurality of switching messages arrive at the AP in a disordered way, the AP establishes communication with the main AC according to the switching message with the largest numerical value of the connection serial numbers in the switching messages, can accurately and effectively establish communication with the correct main AC, shorten the disconnection time of the AP, and avoid the problem that the AP is connected with the wrong AP, therefore, the problem that when AC hot standby switching cannot be effectively processed in a wireless access system with a thin AP architecture, the switching CAPWAP tunnel messages arrive at the AP out of order, the AP cannot be correctly connected to the main AC, and the disconnection time of the AP is prolonged can be solved.

The technical solution of the embodiment of the present invention is explained in detail below.

Fig. 3 shows a block diagram of a wireless access system provided by an embodiment of the present invention, which includes: a first AC31, a second AC32, and AP 33; wherein,

the first AC31 is used for judging whether the first AC is a main AC after connection is established for the first time or whether the first AC is a main AC after AC hot standby switching; under the condition that the first AC31 judges and confirms that the first AC is the main AC after connection is established for the first time, the main AC, namely the first AC31, and the standby AC, namely the second AC32 negotiate to determine a connection serial number, and the connection serial number is stored; the first AC31 sends a switching message to the access point AP33, and the switching message carries a connection sequence number; when the first AC31 judges and confirms that the main AC is the main AC after the AC hot standby switching, the main AC after the switching, namely the first AC31 increases the connection serial number stored by the first AC by a fixed value and stores the increased connection serial number; and, the first AC31 carries the increased connection sequence number in the handover message and sends it to the AP 33; after the switched AC (first AC 31) reestablishes communication with the switched standby AC (second AC 32), the switched AC, namely the first AC31 sends the stored connection serial number to the second AC32, negotiates with the second AC32 and determines a consistent connection serial number, and stores the connection serial number;

the second AC32 is used for judging whether the second AC is a standby AC after connection is established for the first time or whether the second AC is a standby AC after AC hot standby switching; under the condition that the second AC32 judges and confirms that the second AC is the standby AC after the connection is established for the first time, the standby AC, namely the second AC32, negotiates with the main AC, namely the first AC31 to determine a connection serial number, and stores the connection serial number; when the second AC32 determines that the second AC is the standby AC after the AC hot standby switching, the switched standby AC, that is, the second AC32 receives the connection serial number from the first AC31 after the communication is reestablished with the switched main AC, that is, the first AC31, negotiates with the first AC31 and determines a consistent connection serial number, and stores the connection serial number;

and the AP33 is used for sequentially storing the connection sequence numbers in the received switching messages after the CAPWAP tunnels are respectively established with the first AC31 and the second AC32, and establishing communication with the main AC according to the switching message in which the stored connection sequence number and the connection sequence number with the largest value in the connection sequence numbers of the received switching messages are located.

Example one

The working principle of the main AC is explained below.

Fig. 4 shows a working flowchart of an AC hot standby switching method provided in an embodiment of the present invention, that is, the working principle of a main AC, where the method includes:

step 401, the AC determines whether the AC is the main AC after the connection is first established or the main AC after the AC hot standby is switched, and if the AC is determined to be the main AC after the connection is first established, the process proceeds to step 402, and if the AC is determined to be the main AC after the AC hot standby is switched, the process proceeds to step 405;

step 402, under the condition that the AC judges and confirms that the AC is the main AC after the connection is established for the first time, the main AC and the standby AC negotiate to determine a connection serial number;

specifically, the main AC generates a connection serial number of a random number, and sends the connection serial number to the standby AC; the main AC receives a connection serial number of a random number generated by the standby AC; the main AC selects the connection serial number with a larger value from the connection serial numbers of the main AC and the standby AC as the connection serial number determined by negotiation;

step 403, the main AC saves the connection serial number;

step 404, the main AC carries the determined connection sequence number in a handover message and sends the handover message to the access point AP; wherein, the connection serial number is saved by the AP;

step 405, under the condition that the AC determines that the AC is the main AC after the AC hot standby switching, the main AC after the switching increases the connection serial number stored by the main AC by a fixed value; the size of the fixed numerical value can be set according to the needs of a specific application scene, and the fixed numerical value is agreed in both the main AC and the standby AC, namely the same fixed numerical value is kept in both the main AC and the standby AC in advance;

step 406, the switched main AC stores the increased connection serial number;

step 407, the main AC after switching carries the increased connection sequence number in a switching message to send to the AP, where the connection sequence number stores the received connection sequence numbers in sequence for the AP, and provides a reference for establishing communication with the main AC according to the switching message in which the connection sequence number with the largest value among the connection sequence numbers of the plurality of received switching messages and the connection sequence number stored by the AP are located;

step 408, after the switched main AC reestablishes communication with the switched standby AC, sending a stored connection serial number to the standby AC, negotiating with the standby AC, determining a consistent connection serial number, and storing the connection serial number;

specifically, the switched main AC sends the connection serial number stored by the main AC to the switched standby AC, and receives the connection serial number from the switched standby AC, where the connection serial number of the switched standby AC is the connection serial number stored by the standby AC or a random number connection serial number generated by the standby AC when the connection serial number is not stored by the standby AC; and the main AC after switching takes the connection serial number with larger value in the connection serial numbers stored by the main AC and the standby AC as the connection serial number determined for negotiation.

The working principle of the backup AC will be explained below.

Fig. 5 shows a working flowchart of the AC hot standby switching method provided in the embodiment of the present invention, that is, the working principle of the standby AC includes:

step 501, the AC judges whether the AC is a standby AC after connection is established for the first time or whether the AC is a standby AC after AC hot standby switching, the processing is carried out to step 502 under the condition that the AC is judged and determined to be the standby AC after connection is established for the first time, and the processing is carried out to step 504 under the condition that the AC is judged and determined to be the standby AC after AC hot standby switching;

step 502, under the condition that the backup AC which establishes connection for the first time is judged and confirmed, the backup AC and the main AC negotiate to determine a connection serial number;

specifically, the standby AC generates a connection serial number of a random number and sends the connection serial number to the main AC; the standby AC receives a connection serial number of a random number generated by the main AC; the standby AC selects the connection serial number with a larger value from the connection serial numbers of the main AC and the standby AC as the connection serial number determined by negotiation;

step 503, the standby AC stores the connection serial number; wherein, the connection serial number is sent to the AP by the main AC and stored by the AP;

step 504, under the condition that the self is judged to be the standby AC after the hot standby switching of the AC, the switched standby AC receives the connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiates with the main AC and determines a consistent connection serial number;

specifically, the switched standby AC sends the connection serial number stored by the standby AC to the switched main AC, or a random number connection serial number generated by the standby AC when the connection serial number is not stored by the standby AC is sent to the main AC, and the connection serial number stored by the switched main AC is received; the switched standby AC takes the connection serial number with a larger value in the connection serial numbers of the standby AC and the main AC as the connection serial number determined by negotiation;

the method comprises the steps that a received connection serial number from a main AC is sent to an AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for establishing communication with the main AC according to the connection serial number stored by the AP and a switching message where the connection serial number with the largest value in the connection serial numbers of a plurality of received switching messages is located;

step 505, the standby AC stores the determined connection serial number.

Fig. 6 illustrates an operating principle of an AP provided by an embodiment of the present invention, including:

601, after establishing CAPWAP tunnels with a main AC and a standby AC respectively, the AP stores a connection serial number in a switching message received for the first time, and establishes communication with the main AC according to the switching message;

step 602, after the hot standby switch of the AC occurs, the AP receives a plurality of switching messages in sequence, stores the connection sequence numbers in the plurality of switching messages in sequence, and establishes communication with the main AC according to the switching message in which the connection sequence number with the largest value among the stored connection sequence numbers and the connection sequence numbers in the plurality of received switching messages is located.

Through the processing procedures shown in fig. 3, fig. 4, fig. 5 and fig. 6, after connection is established for the first time or AC hot standby switching occurs, the main/standby ACs negotiate or keep consistent connection serial numbers, and the main AC for each switching increases the value of the connection serial number, so that the value of the connection serial number carried in the switching message by the main AC after switching is greater than the value of the connection serial number carried in the switching message by the standby AC, i.e. the main AC before switching, even if a plurality of times of AC hot standby switching occurs between the main AC and the standby AC in a short time, the main AC before and after switching sends a plurality of switching messages to the AP, and the plurality of switching messages arrive at the AP out of order, the AP establishes communication with the main AC according to the switching message with the largest value of the connection serial number in the switching messages, can correctly and effectively establish communication with the correct main AC, and shorten the time for AP to cut off, the problem that the AP is connected to the wrong AP is avoided, and therefore the problems that when the AC hot standby switching cannot be effectively processed in a wireless access system of the conventional thin AP framework, the AP cannot be correctly connected to the main AC and the cutoff time of the AP is prolonged due to the fact that switching messages arrive at the AP out of order are solved. And after the main AC and the standby AC after the AC hot standby switch reestablish communication, a consistent connection serial number is negotiated and determined, and the connection serial number is stored, so that the connection serial numbers between the main AC and the standby AC can be kept consistent.

The working principle of the main AC and the standby AC is described below by a specific application scenario.

Scene one

In this scenario, a primary connection is established between the primary/secondary ACs, and the processing procedure of the primary connection establishment includes:

step one, a hot standby connection is established between a main AC and a standby AC, and a main-standby relation is negotiated;

step two, the main AC and the standby AC respectively generate a random number connection serial number and respectively send the generated connection serial number to the opposite side, and the main AC or the standby AC selects a connection serial number with a larger value from the generated connection serial number and the received connection serial number as a connection serial number determined by negotiation, for example, the connection serial number is 1;

step three, the main AC and the standby AC respectively save connection serial numbers determined by negotiation;

and step four, the main AC carries the connection sequence number in the switching message and sends the switching message to the AP, and the AP stores and records the connection sequence number in the switching message and establishes communication with the main AC according to the switching message.

In this scenario, the connection sequence number is negotiated between the primary/secondary ACs, saved, and the AP also saves the connection sequence number.

Scene two

The method comprises the following steps that AC hot standby switching is carried out on the basis of a scene one in the scene, an AP is to establish communication with a switched main AC, and the processing process of the scene comprises the following steps:

step one, a standby AC before switching detects that the communication is disconnected with a main AC before switching, and AC hot standby switching is triggered, namely the AC is converted into the main AC after switching;

step two, the AC confirms that the AC is the switched main AC, and the switched main AC increases the connection serial number 1 stored in the AC by a fixed value 1 to obtain a connection serial number 2;

step three, the main AC after switching saves the increased connection serial number 2;

step four, the main AC after switching carries the increased connection serial number 2 in a switching message and sends the switching message to the AP;

step five, the main AC after switching sends the connection serial number 2 stored by the main AC to the standby AC after switching, and receives the connection serial number 1 stored by the standby AC after switching; similarly, the standby AC sends the stored connection serial number 1 to the main AC and receives the connection serial number 2 stored in the main AC after self-switching;

step six, the main AC after switching takes the connection serial number 2 with larger value in the connection serial numbers 1 of the main AC and the standby AC stored by the main AC as the connection serial number determined by negotiation; similarly, the switched standby AC also takes the connection serial number 2 as the connection serial number determined by negotiation;

and step seven, after the AP receives the switching message, the AP compares the connection sequence number in the switching message with the value of the connection sequence number stored by the AP, and as the value of the connection sequence number stored by the AP is 1 and the value of the connection sequence number in the received switching message is 2, the AP determines that the value of the connection sequence number carried in the switching message is the largest, the AP establishes communication with the switched main AC according to the received switching message and stores the received connection sequence number 2.

In this scenario, after the AC hot standby switching occurs, the switched main AC increments the connection number and sends the incremented connection number to the AP, so as to indicate that the AP establishes communication with the switched main AC according to the received switching message when the connection number in the received switching message is greater than the connection number stored by the AP.

Scene three

The method comprises the following steps that AC hot standby switching is carried out in the scene on the basis of the scene one, an AP is to establish communication with a switched main AC, and the processing process of the scene comprises the following steps:

after the AP receives the switching message, the AP compares the connection sequence number in the switching message with the value of the connection sequence number stored by the AP, and since the value of the connection sequence number stored by the AP is 1 and the value of the connection sequence number in the received switching message is 2, the AP determines that the value of the connection sequence number carried in the switching message is the largest, the AP establishes communication with the switched main AC according to the received switching message, and stores the received connection sequence number 2.

Step six, after the switched main AC and the switched standby AC reestablish communication, the switched main AC sends the connection serial number 2 stored in the switched main AC to the switched standby AC and receives the connection serial number 5 generated by the switched standby AC;

the main AC before switching is switched due to equipment failure, the main AC before switching is restarted after equipment is replaced, the main AC after switching is determined to be the standby AC after detecting the network, the connection serial number of the main AC after switching is not stored in the equipment replacing process before, then, the standby AC after switching generates a random number connection serial number 5, the standby AC after switching sends the stored connection serial number 5 to the main AC after switching, and receives a connection serial number 2 stored in the main AC after self switching;

step seven, the main AC after switching takes the connection serial number 5 with larger value in the connection serial numbers 2 and 5 of the standby AC stored by the main AC as the connection serial number determined by negotiation; similarly, the switched standby AC also uses the connection serial number 5 as the connection serial number determined by negotiation.

Scene four

Scene four is on the basis of scene one, the AP has already established communication with the main AC, the communication between the main/standby ACs is "flashed", that is, two AC hot standby switching occurs between the main/standby ACs within a very short time, the main ACs switched twice respectively send a switching message to the AP, and the AP has to select a correct main AC to establish communication, and the processing procedure of the scene includes:

step one, after the first AC hot standby switching, the AC confirms that the AC is a main AC after switching, and a fixed value 1 is added to a connection serial number 1 stored in the AC to obtain a connection serial number 2;

step two, the increased connection serial number 2 is stored in the main AC after the first switching;

step three, the increased connection sequence number 2 is carried in a switching message CW1 by the main AC after the first switching and is sent to the AP;

step four, negotiating between the main AC and the standby AC after the first switching to obtain a consistent connection serial number 2, and storing the connection serial number 2, as described in step seven of the above embodiment two;

step five, after the second AC hot standby switching occurs in a short time, the standby AC after the first switching is converted into the main AC after the second hot standby switching, the AC confirms that the AC is the main AC after the switching, and the connection serial number 2 stored in the AC is increased by a fixed value 1 to obtain a connection serial number 3;

step six, the increased connection serial number 3 is stored in the main AC after the second switching;

step seven, the increased connection sequence number 3 is carried in a switching message CW2 by the main AC after the second switching and is sent to the AP;

step eight, due to network congestion or CAPWAP retransmission and other reasons, if CW2 arrives at the AP and CW1 before arriving at the AP, the AP judges that the connection serial number 3 in the CW2 arrived first is larger than the connection serial number 1 stored by the AP, the AP establishes communication with the main AC after the second switching according to the CW2 and stores the connection serial number 3 in the CW2, and the AP judges that the connection serial number 2 in the CW1 arrived after the judgment is smaller than the connection serial number 3 stored by the AP, then the AP discards the CW1 and does not perform CAPWAP tunnel switching; if CW1 arrives at AP and CW2 before arriving at AP, AP judges that the connection serial number 2 in CW1 arriving first is larger than the connection serial number 1 stored by AP, AP establishes communication with the main AC after the first switch according to CW1, AP stores the connection serial number 2 in CW1, and AP judges that the connection serial number 3 of the arriving CW2 terminal is larger than the connection serial number 2 stored by AP, AP establishes communication with the main AC after the second switch according to CW2, and AP stores the connection serial number 3 in CW 2;

step nine, negotiating between the main AC and the standby AC after the second switching to obtain a consistent connection serial number 3, and storing the connection serial number 3, as described in the step seven in the above embodiment two; .

In this scenario, because two times of AC hot standby switching occur between the main AC and the standby AC within a short time, in the two times of switching, the switched main AC all sends a switching message to the AP, and the two times of switching messages sent out may arrive at the AP out of order, according to the embodiment of the present invention, the AP establishes communication with the main AC according to the switching message of the connection sequence number with the largest value among the stored connection sequence numbers and the connection sequence numbers of the received switching messages, because the connection sequence number is incremented by the main AC in the past AC hot standby switching, the connection sequence number with the largest value indicates that the AC hot standby switching corresponding to the connection sequence number is the latest switching, then the AP selects the switching message according to the value of the connection sequence number to establish connection with the main AC, and can select the correct main AC, thereby being able to solve the problem in the wireless access system of the existing thin AP architecture, when the AC hot standby switching cannot be effectively processed, the problem that the AP cannot be correctly connected to the main AC and the disconnection time of the AP is prolonged after the switching message arrives at the AP out of order is caused. .

Based on the same inventive concept, the embodiment of the invention also provides an AC hot standby switching device, and the device is located in the AC.

Fig. 7 is a block diagram illustrating a structure of an AC hot standby switching device according to an embodiment of the present invention, where the device may be located in a main AC, and the device includes:

a judging module 71, a determining module 72, a storing module 73, a sending module 74, a connection sequence number increasing module 75 and a negotiating module 76; wherein,

a judging module 71, configured to judge whether the AC to which the device belongs is a main AC after the initial connection is established or a main AC after the AC hot standby is switched;

a determining module 72, connected to the determining module 71, configured to negotiate with the standby AC to determine a connection sequence number when the determining module 71 determines that the AC to which the device belongs is the main AC after the first connection is established;

specifically, the determining module 72 generates a connection serial number of a random number, and sends the connection serial number to the standby AC; receiving a connection serial number of a random number generated by a standby AC; the determining module 72 selects the connection serial number with a larger value from the generated connection serial number and the connection serial number of the standby AC as the connection serial number determined by negotiation;

a saving module 73, connected to the determining module 72 and the negotiating module 76, for saving the connection sequence number determined by the determining module 72 and saving the connection sequence number determined by the negotiating module 76;

a sending module 74, connected to the determining module 72, configured to send the connection sequence number determined by the determining module 72 to the AP in a handover message, where the connection sequence number is stored by the AP; the connection sequence number added by the connection sequence number adding module 75 is carried in a switching message and sent to the AP, the connection sequence number is a switching message in which the AP sequentially stores the received connection sequence numbers, and a reference is provided for establishing communication with the main AC according to the connection sequence number stored by the AP and the switching message in which the connection sequence number with the largest value among the connection sequence numbers of the received switching messages is located;

a connection sequence number increasing module 75, connected to the judging module 71 and the storing module 73, for increasing the connection sequence number stored in the storing module 73 by a fixed value when the judging module 71 judges that the device AC is the main AC after the AC hot standby switching;

a negotiation module 76, connected to the judgment module 71 and the storage module 73, configured to, when the judgment module 71 judges that the main AC after the AC hot standby is switched, send the connection serial number stored by the storage module 73 to the standby AC after the switched main AC reestablishes communication with the switched standby AC, negotiate with the standby AC, and determine a consistent connection serial number;

specifically, the negotiation module 76 sends the connection serial number stored in the storage module 73 to the switched standby AC, and receives the connection serial number from the switched standby AC, where the connection serial number of the switched standby AC is the connection serial number stored in the standby AC or a random number connection serial number generated by the standby AC when the connection serial number is not stored in the standby AC; the determination storage module 73 takes the connection sequence number with the larger value of the connection sequence number stored in the storage module 73 and the connection sequence number of the standby AC as the connection sequence number determined by negotiation.

The working principle of the device shown in fig. 7 is shown in fig. 4, and will not be described in detail here.

Through the device shown in fig. 7, the AP can correctly and effectively establish communication with the correct main AC through the connection serial number, the AP disconnection time is shortened, and the problem that the AP is connected to the wrong AP is avoided, so that the problem that the AP cannot be correctly connected to the main AC and the disconnection time of the AP is prolonged due to the fact that switching messages arrive at the AP out of order when the AC hot standby switching cannot be effectively handled in the wireless access system of the conventional thin AP architecture can be solved.

Fig. 8 is a block diagram illustrating a structure of an AC hot standby switching device according to an embodiment of the present invention, where the device may be located in a standby AC, and the device is based on the device illustrated in fig. 7, and further includes: a judging module 81, a determining module 82, a negotiating module 83 and a storing module 84; then the process of the first step is carried out,

the determining module 81 is further configured to: judging whether the device AC is a standby AC after connection is established for the first time or whether the device AC is a standby AC after AC hot standby switching;

a determining module 82, connected to the judging module 81, configured to negotiate with the main AC to determine a connection sequence number when the judging module 81 judges that the device AC is the standby AC after connection is first established; wherein, the connection serial number is sent to the AP by the main AC and stored by the AP;

specifically, the determining module 82 generates a connection serial number of a random number, and sends the connection serial number to the main AC; receiving a connection sequence number of a random number generated by a main AC; selecting a connection serial number with a larger value from the connection serial numbers of the main AC and the connection serial numbers generated by the main AC as a connection serial number determined by negotiation;

a negotiation module 83, connected to the determination module 81, configured to receive a connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiate with the main AC, and determine a consistent connection serial number, when the determination module 81 determines that the AC to which the device belongs is the standby AC after the AC hot standby switching; the method comprises the steps that a received connection serial number from a main AC is sent to an AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for communication between the AP and the main AC according to the connection serial number stored by the AP and a switching message where the connection serial number with the largest value in the connection serial numbers of a plurality of received switching messages is located;

specifically, the negotiation module 83 is further connected to the storage module 84, and sends the connection serial number stored in the storage module 84 to the switched main AC, or in a case that the storage module 84 does not store the connection serial number, negotiates a random number connection serial number generated by the module 83, sends the generated connection serial number to the main AC, and receives the connection serial number stored in the switched main AC; the connection serial number with a larger value in the connection serial numbers of the main AC and the connection serial numbers stored in the storage module 84 is used as the connection serial number determined by negotiation, or the connection serial number with a larger value in the connection serial numbers of the main AC and the connection serial numbers generated by the negotiation module 83 is used as the connection serial number determined by negotiation;

a saving module 84, connected to the determining module 82 and the connection sequence number increasing module 83, configured to save the connection sequence number determined by the determining module 82, and save the connection sequence number determined by the negotiating module 83.

The working principle of the device shown in fig. 8 is shown in fig. 5, and will not be described in detail here.

Through the device shown in fig. 8, the function of the standby AC can be realized, and the AP can correctly and effectively establish communication with the correct main AC through the connection serial number, so that the disconnection time of the AP is shortened, and the problem that the AP is connected to the wrong AC is avoided, thereby solving the problem that the AP cannot be correctly connected to the main AC and the disconnection time of the AP is prolonged because the switching message arrives at the AP out of order when the AC hot standby is not effectively handled in the wireless access system of the conventional thin AP architecture.

Example two

An embodiment of the present invention further provides an AC hot standby switching method, as shown in fig. 9, where the method is applied to a main AC, and the method further includes, on the basis of the method shown in fig. 4, the following processing procedures:

step 901, the main AC after the AC hot standby switching increases a connection serial number determined by negotiation with the standby AC by a fixed value;

step 902, the increased connection serial number is saved by the main AC after the AC hot standby switching;

step 903, when a new AP is connected to the main AC, the main AC carries the saved increased connection sequence number in a handover message and sends the handover message to the new AP.

An embodiment of the present invention further provides an AC hot standby switching method, as shown in fig. 10, where the method is applied in standby AC, and on the basis of the method shown in fig. 5, the method further includes the following processing procedures:

1001, adding a fixed numerical value to a connection serial number determined by negotiation between a standby AC and a main AC after the AC hot standby switching;

step 1002, the switched standby AC stores the increased connection serial number.

Through the above processing procedures, it can be known that, if the device is replaced without a device failure in the main AC or the standby AC, after the AC hot standby switching, the connection serial number issued by the main AC to the AP is the connection serial number added by odd number, and the main/standby AC negotiates a connection serial number after reestablishing communication and adds the connection serial number again, that is, under the condition that communication is stored between the main AC and the standby AC, the main/standby AC stores the connection serial number added by even number, when a new AP is connected to the AC, the connection serial number issued by the AC to the AP is the connection serial number added by even number, so that, when the connection serial number received by the AP is the connection serial number added by odd number, it indicates that one AC hot standby switching has occurred, the AP has performed CAPWAP tunnel switching, and when the connection serial number received by the AP is the connection serial number added by even number, it indicates that the AP established communication with the main AC under the normal condition of the main/standby AC communication, therefore, the number of times of the AC hot standby switching can be searched and determined through the connection serial number received by the AP, and reference is provided for fault searching.

Based on the same inventive concept, an embodiment of the present invention further provides an AC hot standby switching device, which is located in an AC, and has the same structure as the device shown in fig. 7, except that:

a connection sequence number increment module 75, further configured to: the negotiation module 76 saved by the saving module 73 negotiates to determine a connection sequence number and increases the connection sequence number by a fixed value;

the saving module 73 is further configured to save the connection serial number increased by the connection serial number increasing module 75;

the sending module 74 is further configured to carry the connection sequence number stored by the storing module 73 in the handover message and send the handover message to the new AP when the new AP is connected to the main AC.

Through the device, the AC can also issue the connection serial number added with odd times to the AP after the AC hot standby switching, and the AC issues the connection serial number added with even times to a new AP under the condition that the communication is stored between the main AC and the standby AC, so that the times of the AC hot standby switching can be searched and determined through the connection serial numbers received by the AP, and reference is provided for fault searching.

Based on the same inventive concept, an embodiment of the present invention further provides an AC hot standby switching device, which is located in an AC, and has the same structure as the device shown in fig. 8, except that:

a negotiation module 83, further configured to: when the AC to which the device belongs is the standby AC after the hot standby switching of the AC, the connection sequence number determined by the negotiation module 83 stored in the storage module 84 through negotiation is increased by a fixed value;

the saving module 84 is further configured to save the connection sequence number incremented by the negotiation module 83;

through the device, the function of AC standby can be realized, the AC can also be issued to the AP after the AC hot standby is switched, the odd-numbered connection serial number is added, and the AC is issued to the new AP and the even-numbered connection serial number is added under the condition that communication is stored between the main AC and the standby AC, so that the frequency of the AC hot standby switching can be searched and determined through the connection serial number received by the AP, and reference is provided for fault searching.

To sum up, in the embodiments of the present invention, after a connection is established for the first time or an AC hot standby switch occurs, the main/standby ACs negotiate or keep consistent connection serial numbers, and the main AC for each switch increments the value of the connection serial number, so that the value of the connection serial number carried in the switch message by the main AC after the switch is greater than the value of the connection serial number carried in the switch message by the standby AC, that is, the main AC before the switch, even though a plurality of times of AC hot standby switches occur between the main AC and the standby AC in a short time, the main AC before and after the switch sends a plurality of switch messages to the AP, and the plurality of switch messages arrive at the AP in a disordered manner, the AP establishes communication with the main AC according to the switch message with the largest value of the connection serial number in the switch messages, and can accurately and effectively establish communication with the correct main AC, shorten the disconnection time of the AP, and avoid the problem that the AP is connected to the wrong AP, thereby solving the problem in the wireless, when the AC hot standby switching cannot be effectively processed, the problem that the AP cannot be correctly connected to the main AC and the disconnection time of the AP is prolonged after the CAPWAP tunnel switching message arrives at the AP out of order is caused.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

In addition, each functional unit in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for switching hot standby of a wireless controller AC is characterized by comprising the following steps:

the AC judges whether the AC is a main AC after connection is established for the first time or whether the AC is a main AC after AC hot standby switching;

under the condition that the AC judges that the AC is the main AC after the connection is established for the first time, the main AC and the standby AC negotiate to determine a connection serial number and store the connection serial number;

the main AC carries the determined connection sequence number in a switching message and sends the switching message to an Access Point (AP); wherein, the connection serial number is saved by the AP;

under the condition that the AC judges and confirms that the AC is the main AC after the AC hot standby switching, the main AC after the switching increases the connection serial number stored by the AC by a fixed value, and stores the increased connection serial number; and,

the main AC after switching carries the increased connection serial number in a switching message and sends the switching message to the AP, wherein the connection serial number is the switching message in which the AP sequentially stores the received connection serial numbers, and the main AC establishes communication with the main AC for reference according to the connection serial number stored by the AP and the connection serial number with the largest value in the connection serial numbers of the received switching messages;

and after the switched main AC and the switched standby AC reestablish communication, sending the stored connection serial number to the standby AC, negotiating with the standby AC to determine a consistent connection serial number, and storing the connection serial number.

2. The method according to claim 1, wherein the negotiating between the main AC and the standby AC to determine the connection sequence number when the AC determines that the AC itself is the main AC after the connection is first established includes:

the main AC generates a connection serial number of a random number and sends the connection serial number to the standby AC;

the main AC receives a connection serial number of a random number generated by the standby AC;

and the main AC determines the connection serial number with a larger value in the connection serial numbers generated by the main AC and the standby AC as the connection serial number obtained by negotiation.

3. The method according to claim 1, wherein negotiating with the standby AC and determining a consistent connection number after the switched main AC reestablishes communication with the switched standby AC, specifically comprises:

the switched main AC sends the connection serial number stored by the main AC to the switched standby AC and receives the connection serial number from the switched standby AC, wherein the connection serial number of the switched standby AC is the connection serial number stored by the standby AC or a random number connection serial number generated by the standby AC under the condition that the connection serial number is not stored by the standby AC;

and the main AC after switching takes the connection serial number with larger value in the connection serial numbers stored by the main AC and the standby AC as the connection serial number determined by negotiation.

4. The method according to any one of claims 1 to 3, wherein after the switched primary AC and the standby AC negotiate to determine a consistent connection sequence number and store the connection sequence number, the method further comprises:

the main AC increases the saved connection serial number determined by negotiation by a fixed numerical value and saves the increased connection serial number; when a new AP is connected to the main AC, the main AC carries the stored connection sequence number in the switching message and sends the switching message to the new AP.

5. A method for switching hot standby of a wireless controller AC is characterized by comprising the following steps:

the AC judges whether the AC is a standby AC after connection is established for the first time or whether the AC is a standby AC after AC hot standby switching;

under the condition that the AC judges and confirms that the AC is the standby AC after the connection is established for the first time, the standby AC negotiates with the main AC to determine a connection serial number, and the connection serial number is stored; wherein, the connection serial number is sent to the AP by the main AC and stored by the AP;

under the condition that the AC judges that the AC is the standby AC after the AC hot standby switching, the switched standby AC receives a connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiates with the main AC to determine a consistent connection serial number, and stores the connection serial number; the received connection serial number from the main AC is sent to the AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for establishing communication with the main AC according to the switching message where the connection serial number with the largest value in the connection serial numbers of the plurality of switching messages stored by the AP is located.

6. The method according to claim 5, wherein the AC negotiates with the primary AC to determine the connection sequence number when determining that the AC itself is the backup AC after the connection is first established, and specifically includes:

the standby AC generates a connection serial number of a random number and sends the connection serial number to the main AC; the standby AC receives a connection serial number of a random number generated by the main AC; and the standby AC determines the connection serial number with a larger value in the connection serial numbers of the main AC and the standby AC as the connection serial number obtained by negotiation.

7. The method according to claim 5, wherein the AC receives the connection serial number from the main AC, negotiates with the main AC and determines a consistent connection serial number when determining that the AC is the standby AC after the AC hot standby switching, and specifically includes:

the switched standby AC sends the connection serial number stored by the standby AC to the switched main AC, or a random number connection serial number generated by the standby AC under the condition that the connection serial number is not stored by the standby AC, sends the generated connection serial number to the main AC, and receives the connection serial number stored by the switched main AC;

and the switched standby AC takes the connection serial number with a larger value in the connection serial numbers of the standby AC and the main AC as the connection serial number determined by negotiation.

8. The method according to any one of claims 5 to 7, wherein after the switched standby AC negotiates with the primary AC to determine a consistent connection number, and stores the connection number, the method further comprises:

and increasing the saved connection sequence number determined by negotiation by a fixed value, and saving the increased connection sequence number.

9. A wireless controller AC hot standby switching device, comprising: the device comprises a judging module, a determining module, a storing module, a sending module, a connection sequence number increasing module and a negotiation module; wherein,

the judging module is used for judging whether the AC to which the device belongs is a main AC after the first connection is established or a main AC after the hot standby of the AC;

the determining module is configured to negotiate with the standby AC to determine a connection sequence number when the determining module determines that the AC to which the device belongs is the main AC after the first connection is established;

the storage module is used for storing the connection serial number determined by the determination module; saving the connection serial number increased by the connection serial number increasing module; storing the connection serial number determined by the negotiation module;

the sending module is configured to send the connection sequence number determined by the determining module to the AP in a handover message, where the connection sequence number is stored by the AP; the connection serial number increased by the connection serial number increasing module is carried in a switching message and sent to the AP, the connection serial number is the switching message in which the AP sequentially stores the received connection serial numbers, and the communication with the main AC is established for reference according to the connection serial number stored by the AP and the switching message in which the connection serial number with the largest value in the connection serial numbers of the received switching messages is located;

the connection sequence number increasing module is used for increasing the connection sequence number stored by the storage module by a fixed value under the condition that the judging module judges that the AC to which the device belongs is the main AC after the AC hot standby switching;

and the negotiation module is used for sending the connection serial number stored by the storage module to the standby AC after the communication between the switched main AC and the switched standby AC is reestablished under the condition that the judgment module judges the main AC after the AC hot standby switching, negotiating with the standby AC and determining a consistent connection serial number.

10. The apparatus according to claim 9, wherein the determining module, when the determining module determines that the AC to which the apparatus belongs is a primary AC after the first connection is established, negotiates with a standby AC to determine a connection sequence number, and is specifically configured to:

generating a connection serial number of a random number, and sending the connection serial number to the standby AC;

receiving a connection serial number of a random number generated by a standby AC;

and determining the connection serial number with a larger value in the generated connection serial number and the connection serial number of the standby AC as the connection serial number obtained by negotiation.

11. The apparatus according to claim 9, wherein the determining module, when the determining module determines that the AC to which the apparatus belongs is a main AC after the AC hot standby is switched, determines a connection sequence number with a larger value from among connection sequence numbers respectively stored in the main AC and the standby AC, and is specifically configured to:

sending the connection serial number stored by the storage module to the switched standby AC, and receiving the connection serial number from the switched standby AC, wherein the connection serial number of the switched standby AC is the connection serial number stored by the standby AC or a random number connection serial number generated by the standby AC under the condition that the connection serial number is not stored by the standby AC;

and taking the connection serial number with a larger value in the connection serial numbers stored by the storage module and the connection serial number of the standby AC as the connection serial number determined by negotiation.

12. The apparatus according to any one of claims 9 to 11, wherein the connection sequence number increasing module is further configured to: the connection serial number determined by the negotiation module and stored by the storage module is increased by a fixed value;

the storage module is further configured to store the connection serial number increased by the connection serial number increasing module;

the sending module is further configured to carry the connection sequence number stored by the storing module in a handover message and send the handover message to a new AP when the new AP is connected to the main AC.

13. The device for switching the hot standby of the wireless controller AC is characterized by comprising a judging module, a determining module, a negotiation module and a storage module;

the judging module is used for judging whether the AC to which the device belongs is the standby AC after the connection is established for the first time or whether the AC is the standby AC after the hot standby switching of the AC;

the determining module is configured to negotiate with a main AC to determine a connection serial number when the determining module determines that the AC to which the device belongs is the standby AC after connection is established for the first time, where the connection serial number is sent from the main AC to an access point AP and is stored by the AP;

the negotiation module is configured to, when the judgment module judges that the AC to which the device belongs is the standby AC after the AC hot standby switching, receive a connection serial number from the main AC after the switched standby AC reestablishes communication with the switched main AC, negotiate with the main AC, and determine a consistent connection serial number; the method comprises the steps that a received connection serial number from a main AC is sent to an AP by the main AC, the received connection serial number is sequentially stored for the AP, and reference is provided for communication between the AP and the main AC according to the connection serial number stored by the AP and a switching message where the connection serial number with the largest value in the connection serial numbers of a plurality of received switching messages is located;

the storage module is further configured to store the connection sequence number determined by the determination module, and store the connection sequence number determined by the negotiation module.

14. The apparatus according to claim 13, wherein the determining module, when the determining module determines that the AC to which the apparatus belongs is a standby AC after connection is first established, negotiates with a primary AC to determine a connection sequence number, and is specifically configured to:

generating a connection serial number of a random number, and sending the connection serial number to the main AC; receiving a connection sequence number of a random number generated by a main AC; and selecting the connection serial number with a larger value from the connection serial numbers of the main AC and the connection serial numbers generated by the main AC as the connection serial number determined by negotiation.

15. The apparatus according to claim 13, wherein the negotiating module, when the determining module determines that the AC to which the apparatus belongs is a standby AC after the AC hot standby is switched, negotiates with a main AC to determine a connection sequence number, and is specifically configured to:

sending the connection serial number stored by the storage module to the switched main AC, or under the condition that the storage module does not store the connection serial number, generating a random number connection serial number by the negotiation module, sending the generated connection serial number to the main AC, and receiving the connection serial number stored by the switched main AC;

and taking the connection serial number with a larger value in the connection serial numbers stored in the storage module and the main AC as the connection serial number determined by negotiation, or taking the connection serial number with a larger value in the connection serial numbers generated by the negotiation module and the main AC as the connection serial number determined by negotiation.

16. The apparatus of any one of claims 13 to 15, wherein the negotiation module is further configured to: when the AC to which the device belongs is the standby AC after the hot standby switching of the AC, the connection serial number determined by the negotiation module and stored by the storage module is increased by a fixed value;

the saving module is further configured to: and storing the connection sequence number increased by the negotiation module.

17. A wireless controller comprising a wireless controller AC hot standby switching arrangement according to any of claims 9 to 12, or comprising an AC hot standby switching arrangement according to any of claims 13 to 16.

18. A wireless access system, comprising: the AC of any one of claims 9 to 12, being a first AC, the AC of any one of claims 13 to 16, being a second AC, and the AP of any one of claims 13 to 16; wherein,

the first AC is used for judging whether the first AC is a main AC after connection is established for the first time or whether the first AC is a main AC after AC hot standby switching; under the condition that the first AC judges and confirms that the first AC is the main AC after connection is established for the first time, the main AC and the standby AC negotiate to determine a connection serial number and store the connection serial number; the main AC carries the determined connection sequence number in a switching message and sends the switching message to an Access Point (AP); under the condition that the first AC judges and confirms that the first AC is the main AC after AC hot standby switching, the main AC after switching increases the connection serial number stored by the main AC by a fixed value, and stores the increased connection serial number; and the main AC after switching carries the increased connection sequence number in the switching message and sends the switching message to the AP; after the switched main AC and the switched standby AC reestablish communication, sending a stored connection serial number to the standby AC, negotiating with the standby AC, determining a consistent connection serial number, and storing the connection serial number;

the second AC is used for judging whether the second AC is a standby AC after connection is established for the first time or whether the second AC is a standby AC after AC hot standby switching; under the condition that the second AC judges and confirms that the second AC is the standby AC after the connection is established for the first time, the standby AC and the main AC negotiate to determine a connection serial number and store the connection serial number; under the condition that the second AC judges that the second AC is the standby AC after the AC hot standby switching, the switched standby AC receives the connection serial number from the main AC after the communication is reestablished with the switched main AC, negotiates with the main AC and determines a consistent connection serial number, and stores the connection serial number;

and the AP is used for sequentially storing the connection serial numbers in the received switching messages after the CAPWAP tunnels are respectively established with the first AC and the second AC, and establishing communication with the main AC according to the stored connection serial numbers and the switching message in which the connection serial number with the largest value is located in the connection serial numbers of the received switching messages.