CN105744579A

CN105744579A - Method for switching terminal between APs, switching control apparatus, and access apparatus

Info

Publication number: CN105744579A
Application number: CN201410764859.XA
Authority: CN
Inventors: 李教峰
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-12-11
Filing date: 2014-12-11
Publication date: 2016-07-06
Anticipated expiration: 2034-12-11
Also published as: CN105744579B

Abstract

The invention discloses a method for switching a terminal between APs, a switching control apparatus, and an access apparatus. A controller manages IP address information of the APs in a unified manner and records host AP identification associated with the terminal and current AP identification so as to switch the terminal between the APs. When the terminal roams to a destination AP from a source AP, the terminal requesting to be re-associated with the destination AP, and the destination AP can request the controller to indicate whether to allow the terminal to be associated with the destination AP; and when the controller indicates that the terminal is allowed to be associated with the destination AP, the destination AP neither have to perform user identify authentication on the terminal nor have to re-distribute an IP address to the terminal, and the terminal can be directly associated with the destination AP for accessing to Internet. According to the invention, the efficiency of the terminal in performing AP switching is improved and the communication quality of a wireless network is improved.

Description

Method, switching control and the access device that terminal switches between AP

Technical field

The present invention relates to communication technical field, particularly relate to method, switching control and access device that a kind of terminal switches between AP.

Background technology

WLAN (WirelessLocalAreaNetwork is called for short WLAN) is low with networking cost, access efficiency is high, dispose the features such as flexible, is widely applied.For meeting mass transportation facilities, for instance bus, subway etc., the online demand of passenger above, by affixing one's name to vehicle-mounted access point (AccessPoint is called for short AP) at vehicle upper, adopt WLAN technology to make wireless network cover vehicle, provide service on net for the passenger on vehicle.

On the vehicle of the vehicle-mounted AP of above-mentioned deployment, terminal, after accessing WLAN, still can move, and user wants to the connection kept in terminal moving process with WLAN.Such as, terminal, after WLAN is accessed in bus stop, still is able to access WLAN in bus driving process.Therefore, in the process that terminal location changes, how to keep the connection between terminal and WLAN not interrupt receiving extensive attention.

Now, if terminal is switched to another vehicle-mounted AP by a vehicle-mounted AP, it would be possible to due to the subscriber authentication of the vehicle-mounted AP of purpose and the re-allocation process of IP address in handoff procedure, cause the terminal of terminal data business.Such as, terminal A has accessed WLAN by vehicle-mounted AP1 on bus 1, and obtains Internet protocol (InternetProtocol is called for short IP) address, and now user can access the Internet by this terminal A；When bus 2 is close, or when terminal is moved to bus 2 by bus 1, vehicle-mounted AP2 on bus 2 provides wireless network signal quality more excellent, now, terminal will be switched on this vehicle-mounted AP2, vehicle-mounted AP1 is will cancel in the terminal A IP address distributed before, and terminal A can be re-started authenticating user identification and distribute the process of IP address by vehicle-mounted AP2, and this process would potentially result in the interruption of data service corresponding for terminal A.

As can be seen here, at present in the process that terminal switches between different AP, there is quality of wireless network difference, the problem causing data traffic interruptions.

Summary of the invention

The embodiment of the present invention provides method, switching control and the access device that a kind of terminal switches between AP, in order to solve at present in the process that terminal switches between different AP, there is quality of wireless network difference, the problem causing data traffic interruptions.

The concrete technical scheme that the embodiment of the present invention provides is as follows:

First aspect, the present invention provides a kind of method that terminal switches between access point AP, including: controller receives the purpose AP user state information inquiry request sent, and described user state information inquiry request includes the MAC address of first terminal；The terminal management table of the described controller MAC Address according to described first terminal and described controller, obtains current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；Described controller notifies that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP, and current AP mark corresponding for first terminal described in the terminal management table of described controller is updated to the mark of described purpose AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；Described controller sends inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

In the first possible implementation of first aspect, before described controller receives the described purpose AP user state information inquiry request sent, farther include: controller receives the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；Controller is according to the mark of described source AP and described synchronizing information, the terminal management table of described controller increases the terminal management list item that described first terminal is corresponding, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

The first possible implementation in conjunction with first aspect, in the implementation that the second of first aspect is possible, described controller receives the terminal management table entry deletion request of described purpose AP, and the request of described terminal management table entry deletion includes the MAC Address of described first terminal；MAC Address according to described first terminal and the terminal management table of described controller, described controller obtains the current AP mark that the MAC Address of described first terminal is corresponding；If described current AP mark is identical with the mark of described purpose AP, host AP mark in the terminal management list item that then MAC Address of the described first terminal of described controller acquisition is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；The terminal management list item of the MAC Address that terminal iidentification is described first terminal deleted by described controller from terminal management table.

Second aspect, the present invention provides a kind of method that terminal switches between access point AP, including: source AP receives the switching notice that controller sends, and described switching notice includes the MAC address of first terminal；Described source AP, according to described switching notice, obtains the corresponding terminal association information table of first terminal described in the terminal association information table of described source AP, the User Status in terminal association information table corresponding for described first terminal is updated to handed over state；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status.

In the first possible implementation of second aspect, before source AP receives the switching notice that controller sends, farther include: described source AP receives the association request that described first terminal sends, and comprises association request type in described association request；When described source AP determines described association request type for associating first, described first terminal is carried out authenticating user identification；After described authenticating user identification passes through, described source AP receives the dynamic host configuration protocol DHCP request that described first terminal sends, and described DHCP request includes the MAC Address of described first terminal；Described source AP is from the Internet protocol IP address pool of described source AP, and described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And in the terminal association information table of described source AP, record the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is original user, and User Status is not for switch state.

The first possible implementation in conjunction with second aspect, in the implementation that the second of second aspect is possible, described source AP is that after described first terminal distribution the oneth IP address, described source AP, according to terminal association information table corresponding to described first terminal, generates synchronizing information；Described synchronizing information is sent to described controller by described source AP, notify the described controller mark according to terminal association information table corresponding to described first terminal and described source AP, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

In conjunction with the implementation that the second of second aspect is possible, in the third possible implementation of second aspect, corresponding for described first terminal terminal association information is sent to after described controller by described source AP, and described source AP receives the terminal that described controller sends and rolls off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；It is the terminal association information table of the MAC Address of described first terminal that described source AP deletes terminal iidentification in described terminal association information table, and discharges the described IP address distributing to described first terminal.

In conjunction with the first of second aspect to any one in the third possible implementation, in the 4th kind of possible implementation of second aspect, before described source AP receives the association request that first terminal sends, described source AP receives the IP address information that described controller is described source AP distribution；Or, it is pre-configured with the IP address information of described source AP；Described IP address information includes the IP address pool of described source AP, subnet mask and gateway address.

The third aspect, the present invention provides a kind of method that terminal switches between access point AP, including: purpose AP receives the association request that first terminal sends, and described association request includes association request type；When described purpose AP judges described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the media of described first terminal and visits control MAC Address, so that described controller determines whether that described first terminal switches to described purpose AP；Described purpose AP receives the inquiry response that described controller sends, and described inquiry response includes switching instruction；If described switching is designated as permission switching, described purpose AP allows described first terminal to switch to described purpose AP, and records the terminal association information table that described first terminal is corresponding in the terminal association information table of described purpose AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer.

In the first possible implementation of the third aspect, after described purpose AP allows described first terminal to be switched to described purpose AP by described source AP, farther include: when described purpose AP detects that described first terminal is not in connection status, generating the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；And send the request of described terminal management table entry deletion to described controller, notify that the terminal management list item that described first terminal is corresponding deleted by described controller；Described purpose AP deletes the terminal association information table that described first terminal is corresponding from the terminal association information table of described purpose AP.

Fourth aspect, the present invention provides a kind of switching control, including: receiving unit, for receiving the purpose AP user state information inquiry request sent, described user state information inquiry request includes the MAC address of first terminal；Acquiring unit, for the MAC Address according to described first terminal and terminal management table, obtains current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；Notification unit, for notifying that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP；Updating block, for being updated to the mark of described purpose AP by current AP mark corresponding for first terminal described in terminal management table；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；Transmitting element, for sending inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

In the first possible implementation of fourth aspect, described switching control also includes terminal management information increases unit, is used for: before receiving the described purpose AP user state information inquiry request sent, and receives the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；Mark according to described source AP and described synchronizing information, described terminal management table increases the terminal management list item that described first terminal is corresponding, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

The first possible implementation in conjunction with fourth aspect, in the implementation that the second of fourth aspect is possible, described switching control also includes terminal management information deletion unit, for: receiving the terminal management table entry deletion request of described purpose AP, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；MAC Address according to described first terminal and described terminal management table, obtain the current AP mark that the MAC Address of described first terminal is corresponding；If described current AP mark is identical with the mark of described purpose AP, then obtain the host AP mark in the terminal management list item that the MAC Address of described first terminal is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；The terminal management list item of the MAC Address that terminal iidentification is described first terminal is deleted from terminal management table.

5th aspect, it is provided that a kind of access device, including: receiving unit, for receiving the switching notice that controller sends, described switching notice includes the MAC address of first terminal；Acquiring unit, for according to described switching notice, obtaining the corresponding terminal association information table of first terminal described in the terminal association information table of described access device；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；Updating block, is updated to handed over state for the User Status in the terminal association information table that the first terminal that got by described acquiring unit is corresponding.

In the first possible implementation in the 5th, described access device also includes processing unit, for: before receiving the switching notice that controller sends, receive the association request that described first terminal sends, described association request comprises association request type；When determining described association request type for associating first, described first terminal is carried out authenticating user identification；After described authenticating user identification passes through, receiving the dynamic host configuration protocol DHCP request that described first terminal sends, described DHCP request includes the MAC Address of described first terminal；From the Internet protocol IP address pool of described access device, described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And in the terminal association information table of described access device, record the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, user type is original user, and User Status is not for switch state.

The first possible implementation in conjunction with the 5th aspect, in the implementation that the second in the 5th is possible, described access device also includes transmitting element, for: after distributing an IP address for described first terminal, according to the terminal association information table that described first terminal is corresponding, generate synchronizing information；Described synchronizing information is sent to described controller, notify the described controller mark according to terminal association information table corresponding to described first terminal and described access device, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described access device, and current AP is designated the mark of described access device.

In conjunction with the implementation that the second of the 5th aspect is possible, in the third possible implementation in the 5th, the terminal that also includes described access device rolls off the production line processing unit, for: corresponding for described first terminal terminal association information table is sent to after described controller, receive the terminal that described controller sends and roll off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；Deleting terminal iidentification in described terminal association information table is the terminal association information table of the MAC Address of described first terminal, and discharges the described IP address distributing to described first terminal.

In conjunction with the 5th aspect the first to any one in the third possible implementation, in the 4th kind of possible implementation in the 5th, described access device also includes IP address information acquiring unit, for: before receiving the association request that first terminal sends, receive the IP address information that described controller is the distribution of described access device；Or, it is pre-configured with the IP address information of described access device；Described IP address information includes the IP address pool of access device, subnet mask and gateway address.

6th aspect, the present invention provides a kind of access device, including: receiving unit, for receiving the association request that first terminal sends, described association request includes association request type；Transmitting element, for when judging described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the MAC address of described first terminal, so that described controller determines whether that described first terminal switches to described access device；Described reception unit, is additionally operable to receive the inquiry response that described controller sends, and described inquiry response includes switching instruction；Switch unit, for when described switching is designated as permission switching, it is allowed to described first terminal switches to described access device, and records the terminal association information table that described first terminal is corresponding in the terminal association information table of described access device；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer.

In the first possible implementation in the 6th, the terminal that also includes described access device rolls off the production line processing unit, for: when detecting that described first terminal is not in connection status, generating the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；And send the request of described terminal management table entry deletion to described controller, notify that the terminal management list item that described first terminal is corresponding deleted by described controller；The terminal association information table that described first terminal is corresponding is deleted from the terminal association information table of described access device.

In the embodiment of the present invention, by the IP address information of controller unified management AP, including IP address pool, gateway address and subnet mask, and record the host AP mark of terminal association and the mark of current AP, to realize the terminal switching at AP.The AP that terminal associates first is host AP, and this terminal is authenticated and is this terminal distribution IP address by host AP.If terminal is switched to purpose AP by source AP, request re-associates to purpose AP, purpose AP and can indicate whether to allow this terminal association to purpose AP by request controller；When the mark of this first terminal preserved by controller, and instruction allows this terminal association to purpose AP, this terminal need not be carried out authenticating user identification by purpose AP, also need not redistribute IP address for this terminal, and terminal can access the Internet either directly through purpose AP.Adopt technical solution of the present invention, by increasing controller in AP framework, needed whether the terminal iidentification carrying out the terminal of AP switching is saved in this controller by controller inquiry, if being saved in this controller, then allow terminal to switch between the aps, and access the Internet either directly through purpose AP, without the process that authenticating user identification and IP address reassign, thus improve terminal to carry out the efficiency of AP switching, effectively prevent the interruption of data service, improve wireless communication quality.

Accompanying drawing explanation

Fig. 1 is WLAN configuration diagram in the embodiment of the present invention；

Fig. 2 is the flow chart one that in the embodiment of the present invention, terminal switches between AP；

Fig. 3 is the flowchart 2 that in the embodiment of the present invention, terminal switches between AP；

Fig. 4 is the flow chart 3 that in the embodiment of the present invention, terminal switches between AP；

Fig. 5 is the User Status switching schematic diagram that in the embodiment of the present invention, terminal is corresponding；

Fig. 6 is switching control structural representation in the embodiment of the present invention；

Fig. 7 is access device structural representation one in the embodiment of the present invention；

Fig. 8 is access device structural representation two in the embodiment of the present invention；

Fig. 9 is embodiment of the present invention middle controller structural representation；

Figure 10 is AP structural representation one in the embodiment of the present invention；

Figure 11 is AP structural representation two in the embodiment of the present invention.

Detailed description of the invention

In the embodiment of the present invention, by the IP address information of controller unified management AP, including IP address pool, gateway address and subnet mask, and record the host AP mark of terminal association and the mark of current AP, to realize terminal switching between AP.The AP that terminal associates first is host AP, and this terminal is authenticated and is this terminal distribution IP address by host AP.If terminal is roamed to purpose AP by source AP, request re-associates to purpose AP, purpose AP and can indicate whether to allow this terminal association to purpose AP by request controller；When the mark of this terminal preserved by controller, and instruction allows this terminal association to purpose AP, this terminal need not be carried out authenticating user identification by purpose AP, also need not redistribute IP address for this terminal, and terminal can be directly linked to purpose AP and access the Internet.In technical solution of the present invention, when switching between different AP due to terminal, IP address remains unchanged, and solves in the process that terminal switches between different AP, it is impossible to ensure the problem that data service even causes service disconnection.Thus improve terminal to carry out the efficiency of AP switching, effectively prevent the interruption of data service, improve wireless communication quality.

Consulting shown in Fig. 1, for WLAN configuration diagram in the embodiment of the present invention, this WLAN includes a controller and multiple AP；Wherein, controller, for managing IP address pool corresponding for each AP, and record host AP mark and the current AP mark that each terminal accesses, in implementing, this controller can be AC；AP is that the terminal associated first carries out subscriber authentication, distributes IP address, and the terminal for association or re-association first provides addressable local resource or Internet resources.

In the embodiment of the present invention, for the process that terminal switches between AP, arbitrary AP can be source AP relative to different terminals, it is also possible to for the purpose of AP.Such as, in the scene shown in Fig. 1, terminal 1 associates an AP first, is switched to the process of the 2nd AP in terminal 1 from an AP, and for terminal 1, an AP is source AP, AP for the purpose of the 2nd AP；And terminal 4 associates the 2nd AP first, being switched to the process of an AP in terminal 4 from the 2nd AP, for terminal 4, the 2nd AP is source AP, and an AP is purpose AP.

Below in conjunction with the scene shown in Fig. 1, with first terminal for terminal 1 exemplarily, introduce technical solution of the present invention, including: first terminal associates an AP first, when namely an AP is the host AP of first terminal, and the processing procedure of controller and an AP；And first terminal is switched to the 2nd AP from an AP later, a described AP is source AP, for the purpose of described 2nd AP during AP, controller, source AP (AP) and purpose AP (the 2nd AP) processing procedure.

Consulting shown in Fig. 2, for the method flow diagram that switches between access point AP of a kind of terminal that the embodiment of the present invention provides, controller perform, described method includes:

Step 200: controller receives the purpose AP user state information inquiry request sent, described user state information inquiry request includes medium education (MediumAccessControl the is called for short MAC) address of first terminal.

Step 210: the terminal management table of the described controller MAC Address according to first terminal and described controller, obtains current AP mark corresponding to the first terminal mark as source AP.

Step 220: described controller notifies that User Status corresponding for first terminal in the terminal association information table of described source AP is updated to handed over state by described source AP, and current AP mark corresponding for first terminal in the terminal management table of controller is updated to the mark of described purpose AP.

Step 230: described controller sends inquiry response to described purpose AP, this inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow first terminal to be associated with described purpose AP, and in the terminal association information table of described AP, record the terminal association information table that first terminal is corresponding.

Specifically, for terminal 1 shown in above-mentioned Fig. 1 from an AP roaming switch to the scene of the 2nd AP, source AP is an AP, purpose AP is the 2nd AP.

Before step 200, oneth AP and the two AP all sets up with controller after electrifying startup and is connected, particularly as follows: an AP sends the first request for building link to controller, controller sets up the first link between an AP and controller according to this first request for building link, 2nd AP sends the second request for building link to controller, and controller sets up the second link between the 2nd AP and controller according to this second request for building link.

Optionally, if controller is AC, above-mentioned first link and the second link can control and configure (ControlAndProvisioningofWirelessAccessPoints is called for short CAPWAP) tunnel for WAP.

After controller sets up corresponding link with an AP and the 2nd AP respectively, controller is each AP configuration of IP address information respectively, and safeguards the corresponding relation of AP mark and IP address information；Wherein, AP mark includes Electronic Serial Number (ElectronicSerialNumber is called for short ESN) code, MAC Address etc.；IP address information includes IP address pool (can also be IP address field, illustrate in the embodiment of the present invention), gateway address and subnet mask for IP address pool.

Or, the IP address information on each AP can also be pre-configured with, and controller only maintains the corresponding relation of AP mark and IP address information.

The IP address pool of each AP of controller administration is different, namely the IP address pool of each AP of controller administration is not overlapping, and the gateway address of all AP of controller administration is all identical with subnet mask.Such as, the IP address pool of an AP is 192.168.1.2～192.168.1.128, and the IP address pool of the 2nd AP is 192.168.1.130～192.168.1.255；The gateway address of controller is 192.168.1.1, and subnet mask is 255.255.0.0, then the gateway address of AP and the two AP under controller administration is 192.168.1.1, and subnet mask is 255.255.0.0.

Each AP preserves the IP address information that controller is self configuration, even if the connection between AP and controller is interrupt status, AP also is able to as terminal distribution IP address, gateway address and subnet mask.

Adopt technique scheme, each AP under administering for same controller configures identical gateway address and subnet mask, it is easy to the controller IP address information to the IP address information of AP, the terminal accessing this AP and terminal be managed, it is also possible to avoid the service disconnection that terminal causes when carrying out redistributing in AP handoff procedure IP address.

AP can preserve the address state of each IP address in its IP address pool, address state is used for identifying whether IP address currently distributes to user terminal, can include having distributed with unallocated, having distributed expression IP address and be already allocated to user terminal use, unallocated status indicator IP address is not yet assigned to any one user terminal and uses.Optionally, AP can also preserve gateway address and subnet mask, then AP needs to distinguish the IP address in IP address pool, gateway address and subnet mask；Can being distinguished by address style, address style can comprise gateway address, subnet mask and three types of address of theenduser；Wherein, the address style of the IP address in IP address pool is address of theenduser.Such as, AP preserves address information table as shown in table 1, to record the corresponding relation of IP address and address state.

Table 1

IP address	Address style	Address state
			192.168.1.1	Gateway address	NA
255.255.0.0	Subnet mask	NA
			192.168.1.2	Address of theenduser	Distribute
192.168.1.3	Address of theenduser	Distribute
			……	……	……
192.168.1.128	Address of theenduser	Unallocated

Oneth AP receives the association request that first terminal sends, and wherein, comprises association request type in this association request.If the association request type in this association request is for associating first, this first terminal is carried out authenticating user identification by an AP；After authenticating user identification passes through, oneth AP receives the DHCP (DynamicHostConfigurationProtocol that above-mentioned first terminal sends, it is called for short DHCP) request, wherein, comprising first terminal mark in this DHCP request, this first terminal is designated the MAC Address of first terminal；Oneth AP selected address state from the IP address pool of an AP is an IP address of unallocated state, generates dhcp response and sends to first terminal, and described dhcp response includes a described IP address；And the address state of an IP address is updated to and distributes state by an AP；Oneth AP adds the terminal association information table that first terminal is corresponding in the terminal association information table of an AP；And terminal association information table corresponding for first terminal is synchronized to controller.

Above-mentioned association first refers to, first terminal is associated with before an AP in request, it does not have be associated with other any one AP under controller administration.Each AP under AC administration all adopts said method to realize the authenticating user identification to the terminal associated first and address distribution, repeats no more herein.

Terminal association information table is for recording the corresponding relation of terminal iidentification, User Status and user type.Wherein, the terminal association information table that this first terminal is corresponding includes the mark of first terminal, the User Status of first terminal, the user type of first terminal.The mark of this first terminal includes the MAC Address of first terminal, it is also possible to include the IP address of first terminal, i.e. an above-mentioned IP address.Optionally, above-mentioned terminal association information table can also include synchronous regime.

User type represents that first terminal is to close the terminal being coupled to an AP first, or switched to the terminal on an AP by other AP, if first terminal is for associate to an AP first, the user type that then first terminal is corresponding is original user, if first terminal is for be switched on an AP by other AP, then the user type that first terminal is corresponding is roamer.

User Status is used for characterizing whether first terminal occurs AP to switch, when the user type that first terminal is corresponding is original user, the User Status that first terminal is corresponding comprises two types, respectively do not switch with handed over, wherein, if first terminal does not occur AP to switch, then User Status is labeled as and does not switch, if first terminal has occurred and that AP switches, namely roamed to the 2nd AP by an AP, then User Status is labeled as handed over.Further, above-mentioned user type can also comprise the third type, it is Restzustand, this Restzustand does not occur AP to switch for first terminal, but the situation of disconnecting (link is obstructed) between an AP and controller when first terminal rolls off the production line, at this point it is possible to user type is labeled as residual.Additionally, when the user type of first terminal is roamer, owing to it has been determined that first terminal there occurs that AP switches, therefore User Status can be labeled as handed over, it is also possible to be not repeated to be designated handed over, be directly designated NA (sky).

The terminal association information table that synchronous regime is corresponding for characterizing the first terminal preserved in an AP, whether the terminal management list item corresponding with the first terminal preserved in controller synchronizes, and comprises and synchronizes and do not synchronize two states.Wherein, the terminal management list item that the first terminal of synchronization representation the oneth AP is corresponding terminal association information table is corresponding with the first terminal of controller keeps synchronizing；The terminal management list item that terminal association information table that the first terminal of non-synchronization representation the oneth AP is corresponding is not corresponding with the first terminal of controller keeps synchronizing.If first terminal carries out AP switching, the connection between an AP and controller is in interrupt status, or, when the connection between the 2nd AP and controller is in interrupt status, controller does not all allow first terminal to carry out AP switching.Therefore, if controller allows first terminal to carry out AP switching, then show that the terminal management list item that terminal association information table that the above-mentioned first terminal of an AP is corresponding is corresponding with the first terminal of controller has synchronized, therefore, in the embodiment of the present invention, when the User Status that first terminal is corresponding is handed over state, and when user type is original user, it is possible to be not concerned with synchronous regime.Further, if User Status corresponding to first terminal is Restzustand, it was shown that first terminal rolls off the production line, and now, an AP can be not concerned with synchronous regime, it is possible to synchronous regime is set to NA.

Such as, AP preserves the terminal association information table shown in table 2, for recording the corresponding relation between terminal iidentification, user type, User Status and synchronous regime.

Table 2

IP address of terminal	Terminal MAC address	User type	User Status	Synchronous regime
					192.168.1.2	A-A-A	Original user	Do not switch	Do not synchronize
192.168.1.3	B-B-B	Original user	Do not switch	Synchronize
					192.168.1.4	C-C-C	Original user	Handed over	NA
192.168.1.5	E-E-E	Original user	Residual	NA
					192.168.2.200	D-D-D	Roamer	NA	NA

From the above, when first terminal closes first and is coupled to an AP, controller receives the AP synchronizing information sent, and this synchronizing information includes the terminal association information table that first terminal is corresponding；The terminal association information table corresponding according to first terminal and the mark of an AP, record the terminal management list item that first terminal is corresponding in the terminal management table of controller.Terminal management table is for recording the corresponding relation of terminal iidentification, host AP mark, current AP mark；Wherein, the mark of the AP that host AP mark expression terminal associates first, the mark of the AP that current AP mark expression terminal currently associates.If host AP mark is identical with current AP mark, it was shown that terminal does not occur AP to switch, if host AP mark is different with current AP mark, it was shown that terminal has occurred AP to switch.In the terminal management list item that described first terminal is corresponding, terminal iidentification includes the MAC Address of first terminal, and host AP is designated the mark of an AP, and current AP mark is also the mark of an AP.Above-mentioned terminal management table can also include the IP address of terminal, the link identification of host AP, the MAC Address of host AP, the ESN code of host AP, the link identification of current AP, the MAC Address of current AP, current AP the information such as ESN code.Such as, controller preserves terminal management table as shown in table 3.

Table 3

Continue from the above, when first terminal closes first and is coupled to an AP, first terminal sends DHCP request to a described AP, receives and parses through the AP dhcp response sent, obtain the MAC Address of an IP address and the AP comprised in this dhcp response, and preserve to first terminal local；Optionally, in address resolution protocol (AddressResolutionProtocol the is called for short ARP) table that the MAC Address of an IP address and an AP can be preserved to first terminal by first terminal.

Further, when first terminal is associated with an AP first, if the connection between an AP and controller is interrupt status, an AP can also use the IP address information of preservation, distribute IP address for first terminal, and in an AP, preserve the terminal association information table that above-mentioned first terminal is corresponding；By the time, after the connection between an AP and controller recovers normally, terminal association information table corresponding for first terminal is synchronized to controller by an AP again.So, when first terminal associates an AP first, the connection between an instant AP and controller is interrupt status, and first terminal remains able to pass and is coupled to an AP, and accesses the resource on an AP.When connection between an AP and controller is in interrupt status, if first terminal is rolled off the production line by an AP, closed first again later and be coupled to an AP, first terminal will be re-started authentication and distribution IP address by the oneth AP, such as the 2nd IP address, and again preserve the terminal association information table that first terminal is corresponding.After connection between an AP and controller recovers normally, IP address in terminal management list item corresponding to first terminal that controller preserves remain as the first terminal last time roll off the production line before an IP address, then the terminal management list item terminal association information table that the first terminal of current preservation is corresponding with an AP that the first terminal that preserves in controller is corresponding is inconsistent.Now, controller, by the terminal association information table corresponding according to the AP first terminal reported, updates the terminal management list item that the first terminal in controller is corresponding.Adopt technique scheme, during for terminal associated AP first, connection between AP and controller is in the abnormal conditions of interrupt status and proposes solution, the problem that the relevant information of the terminal of controller and AP preservation is inconsistent can be prevented effectively from, it is ensured that the accuracy of the terminal management table preserved in controller.

In the embodiment of the present invention, when first terminal is in moving process, detect that the wireless network signal mass parameter of an AP is lower than the first predetermined threshold value, and the 2nd AP wireless network signal mass parameter higher than the second predetermined threshold value time, first terminal initiates association request to the 2nd AP, and this association request includes association request type；If association request type is re-association, represent that first terminal request re-associates to the 2nd AP.Wherein, include a specific fields in association request, be used for characterizing association request type.In association request, this specific fields is by different values, and sign terminal request is closed first and is coupled to an AP, has still closed and has been coupled to other AP, and currently requested pass is coupled to this AP.Such as, when first terminal closes first and is coupled to an AP, this specific fields is 0000, is used for representing that association request type is for associate first；When this first terminal asks again pass to be coupled to two AP, this specific fields is 0010, is used for representing that association request type is re-association.The value of this specific fields in the association request that AP can be sent by terminal, it is determined that terminal is coupled to this AP for associating first to this AP or series of fortified passes.

When the 2nd AP receives the association request that first terminal sends, determine that this association request type is after re-association, MAC Address according to first terminal, generates user state information inquiry request and sends to controller, and request controller indicates whether that allowing described first terminal to close is coupled to described 2nd AP.

In step 210, the controller MAC Address according to the first terminal in the 2nd AP user state information inquiry request sent, whether the terminal management table of inquiry controller is preserved the MAC Address of first terminal, when determining the MAC Address preserving first terminal, controller obtains the current AP mark that the MAC Address of this first terminal is corresponding.In a step 220, when obtaining the current AP mark identifying an AP corresponding as first terminal, controller notifies that an AP updates terminal association information table corresponding to first terminal in the terminal association information table of a described AP, and updates the terminal management list item that first terminal in terminal management table is corresponding.

Concrete, controller notifies that an AP updates the terminal association information table that in terminal association information table, first terminal is corresponding, including: when controller determines that AP switching occurs first terminal, notifying that an AP is by terminal association information table, the User Status that first terminal is corresponding is revised as handed over state；And synchronous regime corresponding for first terminal is revised as NA；Further, the address state of an IP address corresponding to first terminal is not modified by an AP, to ensure that other-end is not distributed in an IP address corresponding for above-mentioned first terminal by an AP, it is to avoid the problem of IP address conflict.

Concrete, the situation of AP switching is there is for first terminal, controller updates the process of the terminal management list item that first terminal is corresponding in terminal management table and includes: the MAC Address of above-mentioned first terminal searched by controller in terminal association information table；After controller finds the MAC Address of first terminal in terminal management table, current AP mark corresponding for the MAC Address of first terminal is revised as the mark of the 2nd AP.Additionally, when the link identification of current AP corresponding to the MAC Address preserving first terminal in terminal management table, in addition it is also necessary to the link identification of current AP corresponding for the MAC Address of first terminal is updated to the second link.Such as, consult shown in table 3, IP address is the host AP that the first terminal of 192.168.1.3 the is corresponding mark being designated an AP, when first terminal judges to meet switching condition, first terminal request is switched to the 2nd AP by an AP, and controller is according to the 2nd AP user state information inquiry request sent, and current AP mark corresponding for the MAC Address of the first terminal in the terminal management table of controller is updated to the mark of the 2nd AP, and the link identification of current AP is updated to the second link.

Further, when first terminal request re-associates to two AP, if the connection between an AP and controller is interrupt status, the switching in the inquiry response that the 2nd AP receives is designated as and does not allow switching, now, refusal first terminal is associated with the 2nd AP by the 2nd AP.Adopt this technical scheme, it is possible to avoid under these abnormal conditions, the problem that terminal mistake occurs when carrying out AP switching.

In step 230, when controller determines that AP switching occurs first terminal, sending inquiry response to the 2nd AP, comprise switching instruction in this inquiry response, this switching is designated as permission switching, is used for indicating the 2nd AP to allow first terminal to be associated with the 2nd AP；2nd AP adds the terminal association information table that first terminal is corresponding in the terminal association information table of the 2nd AP；Such as, consult shown in table 2, IP address of terminal adds the IP address that first terminal is corresponding, terminal MAC address adds the MAC Address of first terminal, user type is set to roamer, User Status is set to NA, synchronous regime is set to NA.

Further, after the 2nd AP allows first terminal to be associated with the 2nd AP, the 2nd AP sends ARP message to first terminal；First terminal resolves this ARP message, obtains the MAC Address of the 2nd AP comprised in ARP message, and the MAC Address of the AP preserved in first terminal is updated to the MAC Address of the 2nd AP；Optionally, when preserving ARP table in first terminal, first terminal updates above-mentioned ARP table according to the MAC Address of the 2nd AP, thus ensureing the accuracy of the ARP table preserved in first terminal.

Optionally, the lower all AP of controller administration can arrange identical MAC Address, now, when the AP under first terminal is administered by controller switches to two AP, need not update ARP table, thus having saved system signaling alternately and the workload of terminal.

Adopt technique scheme, when terminal carries out AP switching, it is only necessary to detected whether this terminal accesses any one AP except purpose AP under the administration of this controller by controller；When controller determines that this terminal accesses any one AP except purpose AP under the administration of this controller, terminal directly uses this any one AP IP address distributed, it is that terminal redistributes IP address without purpose AP, also again terminal is carried out authenticating user identification without purpose AP, thus shortening terminal to carry out the time of AP switching, it is to avoid the interruption of data service in AP handoff procedure.

Further, when first terminal request re-associates to two AP, if the connection between the 2nd AP and controller is in interrupt status, now, refusal first terminal is carried out AP re-association by the 2nd AP, and namely first terminal cannot be carried out AP handoff procedure.Adopting this technical scheme, be prevented effectively under these abnormal conditions, there is the situation of mistake in terminal when carrying out AP switching.

Further, when first terminal request re-associates to two AP, controller detects when first terminal does not access this controller administration lower any one AP, namely generates and comprises switching and be designated as the inquiry response transmission not allowing switching to the 2nd AP, does not allow first terminal to re-associate to the 2nd AP.

In the embodiment of the present invention, when first terminal does not carry out AP switching, by the heartbeat message between first terminal, oneth AP judges whether first terminal has rolled off the production line, when first terminal switches to two AP, oneth AP no longer detects whether first terminal has rolled off the production line, the 2nd AP judge whether first terminal rolls off the production line by the heartbeat message between first terminal.When first terminal roll off the production line i.e. first terminal be not in connection status time, an AP, the 2nd AP and controller are for the behavior of rolling off the production line of first terminal, and processing procedure is respectively as follows:

If first terminal does not occur AP to switch, and connection that the oneth between AP and controller is normal, then an AP generates the request transmission of terminal management table entry deletion to controller based on the MAC Address of first terminal, and deletes the terminal association information table that in the terminal association information table of an AP, first terminal is corresponding；Controller receives the AP terminal management table entry deletion sent request, and in the terminal management table of controller, search the MAC Address of first terminal carried in the request of this terminal management table entry deletion, and delete the terminal management list item that in terminal management table, first terminal is corresponding.Owing in these cases, first terminal does not occur AP to switch, therefore, it is not related to the 2nd AP renewal to terminal association information table.

Further, when first terminal rolls off the production line, if the connection between an AP and controller is in interrupt status, then an AP directly deletes the terminal association information table that in the terminal association information table of an AP, first terminal is corresponding, and it is released to an IP address of first terminal distribution, it is set to unallocated state by the address state of an IP address.In this case, owing to first terminal does not occur AP to switch, when first terminal rolls off the production line, oneth IP address is reassigned to other terminals associated first and does not all result in IP address conflict problem by the oneth AP, therefore, adopt technique scheme, still be able to ensure the normal data traffic of each terminal in WLAN framework.

nullOr，When first terminal rolls off the production line，If the connection between an AP and controller is in interrupt status，Then when an AP determines that the terminal management list item that first terminal is corresponding reports to controller，User Status corresponding for first terminal is set to Restzustand by the terminal association information table of an AP，And keep the address state of an IP address for having distributed state，Such as，For above-mentioned table 1 and table 2，If first terminal rolls off the production line，Then do not delete the terminal association information table that first terminal is corresponding in table 2，And the address state of IP address corresponding for first terminal is remained distribute state in Table 1，When connection between an AP and controller is reverted to normal condition by interrupt status，Oneth AP and notification controller delete the terminal management list item that in terminal management table, first terminal is corresponding，It is always ensured that in an AP and controller the synchronicity of terminal related information；nullWhen an AP determines that the terminal management list item that first terminal is corresponding does not report to controller，Directly delete the terminal association information table that in the terminal association information table of an AP, first terminal is corresponding，And discharge a distribution IP address to first terminal，It is set to unallocated state by the address state of an IP address，This kind of situation corresponds to first terminal when associating an AP first，The connection of the oneth AP and controller is in interrupt status，And when first terminal rolls off the production line，Oneth AP connects the situation still in interrupt status with controller，When being associated with an AP first due to first terminal，Namely terminal association information table corresponding for above-mentioned first terminal is not sent to controller，Controller does not preserve the terminal management list item that first terminal is corresponding，Therefore，When first terminal rolls off the production line，Oneth AP directly deletes the terminal association information table that in the terminal association information table of an AP, above-mentioned first terminal is corresponding，Controller need not be reported to.

If first terminal has occurred AP to switch, and the connection between the 2nd AP and controller is normal, then when the 2nd AP detects that first terminal is not in connection status, and the 2nd AP MAC Address according to first terminal, send the request of terminal management table entry deletion to controller；Controller is asked according to this terminal management table entry deletion, deletes the terminal management list item that in terminal management table, first terminal is corresponding；Further, the 2nd AP deletes terminal association information table corresponding to first terminal in the terminal association information table of the 2nd AP, and notification controller sends terminal to an AP and rolls off the production line notice, and this terminal rolls off the production line and notifies to include the MAC Address of first terminal；Oneth AP rolls off the production line notice according to the terminal that controller sends, the terminal association information table of an AP is searched the MAC Address of above-mentioned first terminal, and delete the terminal association information table that above-mentioned first terminal is corresponding, and the address state of an IP address corresponding for first terminal is set to unallocated state.

Under above-mentioned first terminal in line process, owing to the connection between an AP and controller is in interrupt status, or the connection between the 2nd AP and controller is in interrupt status, all it is likely to result in the relevant information being directed to first terminal between an AP, controller and the 2nd AP asynchronous, therefore, in order to ensure the synchronicity being directed between the relevant information of first terminal between an AP, controller and the 2nd AP, it is divided into following two situation to realize an AP, synchronizing information between the 2nd AP and controller:

The first situation: first terminal does not occur AP to switch.

If the connection between an AP and controller is in interrupt status, the terminal association information table that in the terminal association information table of the oneth AP deletion the oneth AP, first terminal is corresponding, and the address state of an IP address of distribution to first terminal is set to unallocated state, when then the connection between an AP and controller is reverted to normal condition by interrupt status, terminal association information table corresponding for terminals all in terminal association information table is sent to controller by an AP；Controller detects and comprises the terminal management list item that first terminal is corresponding in the terminal management table in controller, and when terminal association information table corresponding to all terminals that an AP reports does not comprise terminal association information table corresponding to first terminal, then show that this first terminal rolls off the production line, now, the terminal management list item that first terminal in terminal management table is corresponding directly deleted by controller.

If the connection between an AP and controller is in interrupt status, User Status corresponding for first terminal is set to Restzustand by the oneth AP in the terminal association information table of an AP, and keep distribution to the address state of an IP address of first terminal for having distributed state, when then the connection between an AP and controller is reverted to normal condition by interrupt status, an AP sends the request of terminal management table entry deletion to controller；Controller receives the AP terminal management table entry deletion sent request, and obtains the MAC Address of the first terminal comprised in the request of this terminal management table entry deletion；When the terminal management table of controller is preserved the MAC Address of first terminal, the terminal management list item that in the terminal management table of controller deletion controller, first terminal is corresponding.

The second situation: AP switching occurs first terminal.

When the 2nd AP detects that first terminal rolls off the production line, if the connection between the 2nd AP and controller is interrupt status, 2nd AP is by terminal association information table corresponding for first terminal in the terminal association information table of deletion the oneth AP, then the connection between the 2nd AP and controller is reverted to normal condition by interrupt status, terminal association information table corresponding for all terminals in the terminal association information table of the 2nd AP is sent to controller by the 2nd AP, controller detects and includes the terminal management list item that first terminal is corresponding in terminal management table, and in terminal association information table corresponding to all terminals that the 2nd AP sends, when not comprising terminal association information table corresponding to first terminal, the terminal management list item that in terminal management table, first terminal is corresponding deleted by controller.

When the 2nd AP detects that first terminal rolls off the production line, if the connection between the 2nd AP and controller is normal condition, and the connection between an AP and controller is interrupt status, after then the connection between an AP and controller reverts to normal condition, controller sends terminal to an AP and rolls off the production line notice, the terminal association information table that in the terminal association information table of instruction the oneth AP deletion the oneth AP, first terminal is corresponding.

Further, after first terminal is switched to the 2nd AP by an AP, an AP network communication quality detected again more preferably, and when meeting switching condition, first terminal sends association request to an AP, and this association request type is re-association；Oneth AP, according to this association request type, sends User Status inquiry request to controller, comprises the MAC Address of first terminal in this User Status inquiry request；Controller inquiry terminal management table, it is determined that when the current AP that first terminal is corresponding is designated the mark of the 2nd AP, notifies the terminal association information table that in the terminal association information table of the 2nd AP deletion the 2nd AP, first terminal is corresponding；And corresponding for first terminal in the terminal management table of controller current AP mark is updated to the mark of an AP by controller, and generates and comprise switching and be designated as and allow the inquiry response of switching to send to an AP；Oneth AP indicates according to above-mentioned switching, it is allowed to first terminal is associated with an AP；User Status corresponding for first terminal in the terminal association information table of the oneth AP is updated to and does not switch state by the oneth AP.

Corresponding with controller side shown in above-mentioned Fig. 2, consult shown in Fig. 3, for the method flow diagram that switch between access point AP of another kind of terminal that the embodiment of the present invention provides, by source AP (AP) execution, the method includes:

Step 300: source AP receives the switching notice that controller sends, and this switching notice includes the MAC Address of first terminal.

Step 310: source AP, according to above-mentioned switching notice, obtains the terminal association information table that in the terminal association information table of source AP, first terminal is corresponding, the User Status in terminal association information table corresponding for first terminal is updated to handed over state；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status.

Specifically, in the present embodiment, being still example in conjunction with terminal 1 shown in Fig. 1 from an AP roaming switch to the scene of the 2nd AP, this source AP is an AP.

In the embodiment of the present invention, before above-mentioned steps 300, an AP sends request for building link to controller, and notification controller sets up the connection between controller and an AP according to this request for building link；After link establishment between an above-mentioned AP and controller is complete, an AP receives the IP address information that controller is an AP distribution；Or, the IP address information in an AP can also by being manually pre-configured with, and controller only maintains the corresponding relation of AP mark and IP address information；Oneth AP is according to above-mentioned IP address information, and the first terminal for being associated with an AP first distributes IP address.Wherein, above-mentioned IP address information includes IP address pool, gateway address and subnet mask.

Optionally, if controller is AC, the link between an above-mentioned AP and controller can be the tunnel meeting CAPWAP.

Optionally, based on above-mentioned IP address information, an AP is locally generated address information table as shown in table 1.

Concrete, oneth AP is according to IP address information, first terminal for being associated with an AP first distributes IP address, it is: when an AP receives the association request that first terminal sends, determine that when the association request type that this association request includes is associate first, first terminal is carried out authenticating user identification by the oneth AP；After above-mentioned authenticating user identification passes through, an AP receives the DHCP request that first terminal sends；According to this DHCP request, from the IP address pool that the IP address information of an AP comprises, arbitrarily selected address state is an IP address of unallocated state, generates dhcp response and sends to first terminal, and described dhcp response includes a described IP address；And the address state of an IP address is updated to and distributes state by an AP；Oneth AP adds the terminal association information table that first terminal is corresponding in the terminal association information table of an AP；And terminal association information table corresponding for first terminal is synchronized to controller.

When first terminal closes first and is coupled to an AP, controller receives the AP synchronizing information sent, and this synchronizing information includes the terminal association information table that first terminal is corresponding；The terminal association information table corresponding according to first terminal and the mark of an AP, record the terminal management list item that first terminal is corresponding in the terminal management table of controller.Terminal management table is for recording the corresponding relation of terminal iidentification, host AP mark, current AP mark；Wherein, the mark of the AP that host AP mark expression terminal associates first, the mark of the AP that current AP mark expression terminal currently associates.If host AP mark is identical with current AP mark, it was shown that terminal does not occur AP to switch, if host AP mark is different with current AP mark, it was shown that terminal has occurred AP to switch.In the terminal management list item that described first terminal is corresponding, terminal iidentification includes the MAC Address of first terminal, and host AP is designated the mark of an AP, and current AP mark is also the mark of an AP.Above-mentioned terminal management table can also include the IP address of terminal, the link identification of host AP, the MAC Address of host AP, the ESN code of host AP, the link identification of current AP, the MAC Address of current AP, current AP the information such as ESN code.

When first terminal is associated with an AP first, if the connection between an AP and controller is interrupt status, oneth AP can also use the IP address information of preservation, distributes IP address for first terminal, and preserves the terminal association information table that above-mentioned first terminal is corresponding in an AP；By the time, after the connection between an AP and controller recovers normally, terminal association information table corresponding for first terminal is synchronized to controller by an AP again.So, when first terminal associates an AP first, the connection between an instant AP and controller is interrupt status, and first terminal remains able to pass and is coupled to an AP, and accesses the resource on an AP.When connection between an AP and controller is in interrupt status, if first terminal is rolled off the production line by an AP, closed first again later and be coupled to an AP, first terminal will be re-started authentication and distribution IP address by the oneth AP, such as the 2nd IP address, and again preserve the terminal association information table that first terminal is corresponding.After connection between an AP and controller recovers normally, IP address in terminal management list item corresponding to first terminal that controller preserves remain as the first terminal last time roll off the production line before an IP address, then the terminal management list item terminal association information table that the first terminal of current preservation is corresponding with an AP that the first terminal that preserves in controller is corresponding is inconsistent.Now, controller, by the terminal association information table corresponding according to the AP first terminal reported, updates the terminal management list item that the first terminal in controller is corresponding.Adopt technique scheme, during for terminal associated AP first, connection between AP and controller is in the abnormal conditions of interrupt status and proposes solution, the problem that the relevant information of the terminal of controller and AP preservation is inconsistent can be prevented effectively from, it is ensured that the accuracy of the terminal management table preserved in controller.

In step 310, when controller determines that first terminal can carry out AP switching, send switching notice to an AP；User Status corresponding for above-mentioned first terminal, according to this switching notice, is revised as handed over state by the oneth AP in the terminal association information table of an AP；And, the address state of the IP address distributed for first terminal need not be modified by the oneth AP, namely keep the address state of an IP address for distributing state, ensureing that other-end is not distributed in an IP address corresponding for above-mentioned first terminal by an AP, it is to avoid the problem of IP address conflict.

Further, when first terminal request re-associates to two AP, the connection between an AP and controller is interrupt status, or the connection between the 2nd AP and controller is in interrupt status, and refusal first terminal is carried out AP switching by the 2nd AP.Adopting this technical scheme, it is to avoid under these abnormal conditions, there is the situation of mistake in terminal when carrying out AP switching.

Further, when an AP detects that first terminal is not in connection status, if first terminal does not carry out AP switching, then the AP MAC Address according to first terminal, send the request of terminal management table entry deletion to controller；Controller deletes, according to the request of this terminal management table entry deletion, the terminal management list item that in terminal management table, first terminal is corresponding；Oneth AP deletes terminal association information table corresponding to above-mentioned first terminal in the terminal association information table of an AP, and is released to an IP address of first terminal distribution, is set to unallocated state by the address state of an IP address；If first terminal has carried out AP switching, then the 2nd AP sends the request of terminal management table entry deletion and the terminal association information table that in the terminal association information table of the 2nd AP deletion the 2nd AP, first terminal is corresponding to controller；Controller is asked according to this terminal management table entry deletion, generates terminal and rolls off the production line notice, and deletes the terminal management list item that in the terminal management table of controller, first terminal is corresponding, this MAC Address comprising first terminal in notifying that rolls off the production line；Oneth AP receives the terminal that controller sends and rolls off the production line notice, the terminal association information table of an AP is searched the MAC Address of above-mentioned first terminal, and delete the terminal association information table that first terminal in terminal association information table is corresponding, and the address state of the IP address distributed for first terminal is set to unallocated state.

Under above-mentioned first terminal in line process, owing to the connection between an AP and controller is in interrupt status, or the connection between the 2nd AP and controller is in interrupt status, all it is likely to result in the relevant information being directed to first terminal between an AP, controller and the 2nd AP asynchronous, therefore, in order to ensure the synchronicity being directed between the relevant information of first terminal between an AP, controller and the 2nd AP, it is divided into following two situation to realize an AP, synchronization between the 2nd AP and controller:

The first situation: first terminal does not occur AP to switch.

The second situation: AP switching occurs first terminal.

Corresponding with controller side shown in above-mentioned Fig. 2, consult shown in Fig. 4, for the method flow diagram that switch between access point AP of another kind of terminal that the embodiment of the present invention provides, by purpose AP (the 2nd AP) execution, the method includes:

Step 400: purpose AP receives the association request that first terminal sends, and this association request includes association request type.

Step 410: when described purpose AP judges described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the MAC Address of described first terminal, so that described controller determines whether that described first terminal switches to described purpose AP.

Step 420: described purpose AP receives the inquiry response that controller sends, this inquiry response includes switching instruction.

Step 430: if described switching is designated as permission switching, described purpose AP allows described first terminal to be associated with described purpose AP；And in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer, and described User Status is empty.

Specifically, in the present embodiment, being still example in conjunction with terminal 1 shown in Fig. 1 from an AP roaming switch to the scene of the 2nd AP, this purpose AP is the 2nd AP.

Before step 400, the 2nd AP sends request for building link to controller, and notification controller sets up the connection between controller and the 2nd AP according to above-mentioned request for building link；After link establishment is complete, the 2nd AP receives the IP address information that controller is the 2nd AP distribution；Or, the IP address information in the 2nd AP can also be pre-configured with, and controller only maintains the corresponding relation of AP mark and IP address information；2nd AP is according to above-mentioned IP address information, for being associated with the second terminal distribution IP address of this locality first.Wherein, above-mentioned IP address information includes IP address pool, gateway address and subnet mask.

Optionally, if controller is AC, the link between above-mentioned 2nd AP and controller can be the tunnel meeting CAPWAP.

Optionally, the 2nd AP, based on the IP address information of configuration, is locally generated address information table as shown in table 1.

Concrete, 2nd AP, according to IP address information, for being associated with the second terminal distribution IP address of the 2nd AP first, is: when the 2nd AP receives the association request that the second terminal sends, when determining this association request type for associating first, the second terminal is carried out authenticating user identification；After above-mentioned authenticating user identification passes through, the 2nd AP receives the DHCP request that the second terminal sends；According to this DHCP request, from the IP address pool that the IP address information of the 2nd AP comprises, arbitrarily selected address state is the 2nd IP address of unallocated state, generates dhcp response and sends to the second terminal, and described dhcp response includes described 2nd IP address；And the address state of the 2nd IP address is updated to and distributes state by the 2nd AP；2nd AP adds the terminal association information table that the second terminal is corresponding in the terminal association information table of the 2nd AP；And terminal association information table corresponding for the second terminal is synchronized to controller.

When the second terminal is closed first and is coupled to two AP, controller receives the 2nd AP synchronizing information sent, and this synchronizing information includes the terminal association information table that the second terminal is corresponding；The terminal association information table corresponding according to the second terminal and the mark of the 2nd AP, record the terminal management list item that the second terminal is corresponding in the terminal management table of controller.Terminal management table is for recording the corresponding relation of terminal iidentification, host AP mark, current AP mark；Wherein, the mark of the AP that host AP mark expression terminal associates first, the mark of the AP that current AP mark expression terminal currently associates.If host AP mark is identical with current AP mark, it was shown that terminal does not occur AP to switch, if host AP mark is different with current AP mark, it was shown that terminal has occurred AP to switch.In the terminal management list item that described second terminal is corresponding, terminal iidentification includes the MAC Address of the second terminal, and host AP is designated the mark of the 2nd AP, and current AP mark is also the mark of the 2nd AP.Above-mentioned terminal management table can also include the IP address of terminal, the link identification of host AP, the MAC Address of host AP, the ESN code of host AP, the link identification of current AP, the MAC Address of current AP, current AP the information such as ESN code.

In step 410, when first terminal is in moving process, detect that the wireless network signal mass parameter of an AP is lower than the first predetermined threshold value, and the 2nd AP wireless network signal mass parameter higher than the second predetermined threshold value time, association request is initiated to the 2nd AP, request accesses the 2nd AP, and the association request type comprised in this association request is re-association；2nd AP, according to this association request type, the MAC Address according to first terminal, generates user state information inquiry request；This user state information inquiry request is sent to controller by the 2nd AP, and notification controller inquires about which AP that above-mentioned first terminal is connected under controller administration.

In step 420, the controller MAC Address according to the first terminal carried in the 2nd AP user state information inquiry request sent, the MAC Address of above-mentioned first terminal is inquired about from the terminal management table of controller, and determine when the current AP that first terminal is corresponding is an AP, send switching notice to an AP, and current AP mark corresponding for first terminal in the terminal management table of controller is revised as the mark of the 2nd AP.Further, controller sends inquiry response to the 2nd AP；2nd AP is according to the switching instruction comprised in this inquiry response, it may be judged whether allow first terminal to be switched to the 2nd AP by an AP.

In step 430, when above-mentioned switching is designated as permission switching, 2nd AP records the terminal association information table that above-mentioned first terminal is corresponding in the terminal association information table of the 2nd AP, namely in IP address of terminal, add the IP address that above-mentioned first terminal is corresponding, first terminal MAC Address adds the MAC Address of first terminal, user type is set to roamer, User Status is set to NA.

Adopt technique scheme, when terminal carries out AP switching, it is only necessary to detected whether this terminal accesses any one AP under the administration of this controller by controller；When determining that this terminal accesses any one AP under controller noted above administration, it is that terminal redistributes IP address without purpose AP, also without purpose AP, terminal is carried out authenticating user identification, thus shortening terminal to carry out the time of AP switching, avoid the terminal of data service in AP handoff procedure, and decrease the workload of purpose AP.

Further, when first terminal request re-associates to two AP, the connection between an AP and controller is interrupt status, or the connection between the 2nd AP and controller is in interrupt status, and refusal first terminal is carried out AP handoff procedure by the 2nd AP.Adopting this technical scheme, it is to avoid under these abnormal conditions, there is the situation of mistake in terminal when carrying out AP switching.

Further, when the 2nd AP detects that first terminal is not in connection status (namely first terminal rolls off the production line), 2nd AP sends the request of terminal management table entry deletion to controller, and notification controller deletes the terminal management list item that this first terminal is corresponding from terminal management table；And the terminal association information table that in the terminal association information table of notification controller instruction the oneth AP deletion the oneth AP, above-mentioned first terminal is corresponding, and notify that the address state of an IP address is set to unallocated state by an AP；2nd AP deletes the terminal association information table that the first terminal in terminal association information table is corresponding.

Special, for following abnormal conditions, when the 2nd AP detects that first terminal is not in connection status, if the connection between the 2nd AP and controller is in interrupt status, then the 2nd AP deletes the terminal association information table that above-mentioned first terminal is corresponding from the terminal association information table of the 2nd AP.

Further, when connection between the 2nd AP and controller is successful connection state by interrupt status reparation, terminal association information table corresponding for terminals all in terminal association information table is sent to controller by the 2nd AP, notification controller detects and comprises the terminal management list item that first terminal is corresponding in terminal management table, and in terminal association information table corresponding to all terminals that the 2nd AP sends, when not comprising terminal association information table corresponding to first terminal, the terminal management list item that in terminal management table, first terminal is corresponding deleted by controller.

Based on technique scheme, in the terminal association information table that first terminal is corresponding, User Status project change schematic diagram is consulted shown in Fig. 5.Wherein:

0 represents initial state, and now first terminal is associated with an AP first, and now, in the terminal association information table that the AP first terminal preserved is corresponding, synchronous regime is non-synchronous regime, and User Status is not for switch state.

1 represents when the connection between an AP and controller is normal condition, terminal association information table corresponding for first terminal is sent to controller by the oneth AP, the corresponding information making controller and an AP keeps synchronizing, the synchronous regime project that now in an AP, first terminal is corresponding is synchronous regime, and User Status is not for switch state.

2 expressions do not switch non-synchronous regime when first terminal is in, and first terminal is when rolling off the production line, oneth AP deletes the terminal association information table that in terminal association information table, above-mentioned first terminal is corresponding, and the address state of an IP address corresponding for first terminal is set to unallocated state, thus complete release to reclaim an above-mentioned IP address.

3 represent and do not switch under synchronous regime when first terminal is in, first terminal rolls off the production line, and the connection that the oneth between AP and controller is when being normal condition, the request of terminal management table entry deletion is sent to controller, notification controller deletes the terminal management list item that in terminal management table, first terminal is corresponding, and the oneth AP delete the terminal association information table that first terminal is corresponding in terminal association information table, and the address state of an IP address corresponding for first terminal is set to unallocated state, thus complete release to reclaim an above-mentioned IP address.

4 represent and do not switch under synchronous regime when first terminal is in, first terminal carries out AP switching, controller updates the terminal management list item that in terminal management table, first terminal is corresponding, and notify that an AP updates the terminal association information table that in an AP, in terminal association information table, first terminal is corresponding, namely User Status corresponding for first terminal is revised as handed over state by an AP, and the address state of the IP address that above-mentioned first terminal is corresponding is maintained as distributing state.

5 represent that first terminals are in does not switch under synchronous regime, oneth AP detects that this first terminal rolls off the production line, and the connection that the oneth between AP and controller is interrupt status, User Status corresponding for first terminal is set to residual by the oneth AP, and the address state of the IP address that first terminal is corresponding is maintained as distributing state；Or, an AP deletes the terminal association information table that in terminal association information table, first terminal is corresponding.

6 represent that first terminal is under handed over state, when first terminal rolls off the production line, controller notifies that an above-mentioned first terminal of AP has rolled off the production line, then an AP deletes the terminal association information table that in terminal association information table, first terminal is corresponding, and the address state of an IP address corresponding for first terminal is set to unallocated state, thus complete release to reclaim an above-mentioned IP address.In addition, when connection between controller and the 2nd AP is interrupt status, the terminal association information table that in the terminal association information table of the 2nd AP deletion the 2nd AP, first terminal is corresponding, when connection between controller and the 2nd AP reverts to normal condition, 2nd AP is by terminal association information reporting corresponding for all terminals in terminal association information table to controller, controller deletes, according to the terminal association information table that these all terminals are corresponding, the terminal management list item that in terminal management table, first terminal is corresponding, and notify the terminal association information table that in the terminal association information table of AP deletion the oneth AP, first terminal is corresponding.When connection between controller and an AP is interrupt status, the terminal management list item that in terminal management table, first terminal is corresponding deleted by controller；When connection between controller and an AP reverts to normal condition, controller sends terminal to an AP and rolls off the production line notice, notifies the terminal association information table that in an AP deletion terminal association information table, first terminal is corresponding.

7 represent that first terminal is under Restzustand, after link establishment between an AP and controller, the terminal management list item that in the terminal management table of the oneth AP notification controller deletion controller, first terminal is corresponding, and the address state of an IP address corresponding for first terminal is set to unallocated state, thus complete release to reclaim an above-mentioned IP address.

Based on technique scheme, consult shown in Fig. 6, the embodiment of the present invention provides a kind of switching control, including receiving unit 60, acquiring unit 61, notification unit 62, updating block 63, and transmitting element 64, this switching control is disposed on the controller, for realizing the method that the terminal shown in Fig. 2 of the present invention switches between AP.Wherein:

Receiving unit 60, for receiving the purpose AP user state information inquiry request sent, described user state information inquiry request includes the MAC address of first terminal；

Acquiring unit 61, for the MAC Address according to described first terminal and terminal management table, obtains current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；

Notification unit 62, for notifying that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP；

Updating block 63, for being updated to the mark of described purpose AP by current AP mark corresponding for first terminal described in terminal management table；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；

Transmitting element 64, for sending inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

Optionally, described device also includes terminal management information increases unit 65, is used for: before receiving the described purpose AP user state information inquiry request sent, and receives the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；Mark according to described source AP and described synchronizing information, described terminal management table increases the terminal management list item that described first terminal is corresponding, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

Optionally, described device also includes terminal management information deletion unit 66, is used for: receiving the terminal management table entry deletion request of described purpose AP, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；MAC Address according to described first terminal and described terminal management table, obtain the current AP mark that the MAC Address of described first terminal is corresponding；If described current AP mark is identical with the mark of described purpose AP, then obtain the host AP mark in the terminal management list item that the MAC Address of described first terminal is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；The terminal management list item of the MAC Address that terminal iidentification is described first terminal is deleted from terminal management table.

In the present embodiment, do not use up details about the function of described switching control and operation principle, be referred to described in the embodiment of the method for above-mentioned Fig. 2～5.

Based on technique scheme, consulting shown in Fig. 7, the embodiment of the present invention provides a kind of access device, including receiving unit 70, acquiring unit 71, updating block 72；This access device is deployed on the AP of source, for realizing the method that the terminal shown in Fig. 3 of the present invention switches between AP.Wherein:

Receiving unit 70, for receiving the switching notice that controller sends, described switching notice includes the MAC Address of first terminal；

Acquiring unit 71, for according to described switching notice, obtaining the corresponding terminal association information table of first terminal described in the terminal association information table of described access device；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；

Updating block 72, is updated to handed over state for the User Status in the terminal association information table that the first terminal for being got by described acquiring unit 71 is corresponding.

Further, described device also includes processing unit 73, is used for: before receiving the switching notice that controller sends, and receives the association request that described first terminal sends, comprises association request type in described association request；When determining described association request type for associating first, described first terminal is carried out authenticating user identification；After described authenticating user identification passes through, receiving the dynamic host configuration protocol DHCP request that described first terminal sends, described DHCP request includes the MAC Address of described first terminal；From the Internet protocol IP address pool of described access device, described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And in the terminal association information table of described access device, record the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, user type is original user, and User Status is not for switch state.

Further, described access device also includes transmitting element 74, is used for: after distributing an IP address for described first terminal, according to the terminal association information table that described first terminal is corresponding, generate synchronizing information；Described synchronizing information is sent to described controller, notify the described controller mark according to terminal association information table corresponding to described first terminal and described access device, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described access device, and current AP is designated the mark of described access device.

Further, described access device also includes terminal and rolls off the production line processing unit 75, is used for: sent by terminal association information table corresponding for described first terminal to after described controller, receives the terminal that described controller sends and rolls off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；Deleting terminal iidentification in described terminal association information table is the terminal association information table of the MAC Address of described first terminal, and discharges the described IP address distributing to described first terminal.

Further, described device also includes IP address information acquiring unit 76, is used for: before receiving the association request that first terminal sends, and receives the IP address information that described controller is the distribution of described access device；Or, it is pre-configured with the IP address information of described access device；Described IP address information includes the IP address pool of described access device, subnet mask and gateway address.

In the present embodiment, do not use up details about the function of described access device and operation principle, be referred to described in the embodiment of the method for above-mentioned Fig. 2～5.

Based on technique scheme, consulting shown in Fig. 8, the embodiment of the present invention provides another kind of access device, including receiving unit 80, transmitting element 81, and switch unit 82；This access device is deployed on purpose AP, for realizing the method that the terminal shown in Fig. 4 of the present invention switches between AP.Wherein:

Receiving unit 80, for receiving the association request that first terminal sends, described association request includes association request type；

Transmitting element 81, for when judging described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the MAC address of described first terminal, so that described controller determines whether that described first terminal switches to described purpose AP；

Described reception unit 80, is additionally operable to receive the inquiry response that described controller sends, and described inquiry response includes switching instruction；

Switch unit 82, if being designated as permission switching for the switching in described inquiry response, it is allowed to described first terminal is associated with described access device；And in the terminal association information table of described access device, record the terminal association information table that described first terminal is corresponding；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer, and described User Status is empty.

Further, the terminal that also includes described access device rolls off the production line processing unit 83, for: when detecting that described first terminal is not in connection status, generating the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；And send the request of described terminal management table entry deletion to described controller, notify that the terminal management list item that described first terminal is corresponding deleted by described controller；The terminal association information table that described first terminal is corresponding is deleted from the terminal association information table of described access device.

Based on technique scheme, consulting shown in Fig. 9, the embodiment of the present invention also provides for a kind of controller, including processor 90, wireless communication port 91, memorizer 92, and bus 93, for realizing the method that the terminal shown in Fig. 2 of the present invention switches between AP.Wherein:

Processor 90, wireless communication port 91, memorizer 92 is connected with each other by bus 93；Bus 93 can be Peripheral Component Interconnect standard (peripheralcomponentinterconnect, it is called for short PCI) bus or EISA (extendedindustrystandardarchitecture is called for short EISA) bus etc..Described bus can be divided into address bus, data/address bus, control bus etc..For ease of representing, Fig. 9 only represents with a thick line, it is not intended that only have a bus or a type of bus.

Memorizer 92, is used for depositing program.Specifically, program can include program code, and described program code includes computer-managed instruction.Memorizer 92 is likely to comprise random access memory (randomaccessmemory is called for short RAM), it is also possible to also include nonvolatile memory (non-volatilememory), for instance at least one disk memory.

Wireless communication port 91, for receiving the purpose AP user state information inquiry request sent, described user state information inquiry request includes the MAC address of first terminal.Processor 90, for running the program deposited in described memorizer 92, performs following operation:

MAC Address according to described first terminal and terminal management table, obtain current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；Notification unit, for notifying that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP；Current AP mark corresponding for first terminal described in terminal management table is updated to the mark of described purpose AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status.

Described wireless communication port 91, it is additionally operable to send inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

Further, described wireless communication port 91, it is additionally operable to: before receiving the described purpose AP user state information inquiry request sent, receives the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；

Further, described processor 90, it is additionally operable to: the described synchronizing information received according to described wireless communication port 91, and the mark of described source AP, increasing the terminal management list item that described first terminal is corresponding in described terminal management table, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

Further, described wireless communication port 91, it is additionally operable to: receiving the terminal management table entry deletion request of described purpose AP, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；

Further, described processor 90, it is additionally operable to: according to the MAC Address of described first terminal and described terminal management table, obtain the current AP mark that the MAC Address of described first terminal is corresponding；If described current AP mark is identical with the mark of described purpose AP, then obtain the host AP mark in the terminal management list item that the MAC Address of described first terminal is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；The terminal management list item of the MAC Address that terminal iidentification is described first terminal is deleted from terminal management table.

Described memorizer 92, is additionally operable to storage terminal management list item.

Above-mentioned processor 90 can be general processor, including central processing unit (CentralProcessingUnit is called for short CPU), network processing unit (NetworkProcessor is called for short NP) etc.；Can also is that digital signal processor (DSP), special IC (ASIC), field programmable gate array (FPGA) or other PLDs, discrete gate or transistor logic, discrete hardware components.

In the present embodiment, do not use up details about the function of described controller and operation principle, be referred to described in the embodiment of the method for above-mentioned Fig. 2～5.

Based on technique scheme, consulting shown in Figure 10, the embodiment of the present invention also provides for a kind of AP, including processor 100, wireless communication port 101, memorizer 102, and bus 103, wherein:

Processor 100, wireless communication port 101, memorizer 102 is connected with each other by bus 103；Bus 103 can be pci bus or eisa bus etc..Described bus can be divided into address bus, data/address bus, control bus etc..For ease of representing, Figure 10 only represents with a thick line, it is not intended that only have a bus or a type of bus.

Memorizer 102, is used for depositing program.Specifically, program can include program code, and described program code includes computer-managed instruction.Memorizer 102 is likely to comprise RAM, it is also possible to also include nonvolatile memory, for instance at least one disk memory.

Wireless communication port 101, for receiving the switching notice that controller sends, described switching notice includes the MAC address of first terminal；

Processor 100, runs the program deposited in described memorizer 102, performs following operation:

According to described switching notice, obtain the corresponding terminal association information table of first terminal described in the terminal association information table of described AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, and the User Status in terminal association information table corresponding for described first terminal is also updated to handed over state by corresponding relation between User Status.

Further, described wireless communication port 101, it is additionally operable to: before receiving the switching notice that controller sends, receives the association request that described first terminal sends, described association request comprises association request type；

Further, described processor 100, it is additionally operable to: when determining described association request type for associating first, described first terminal is carried out authenticating user identification；After described authenticating user identification passes through, receiving the dynamic host configuration protocol DHCP request that described first terminal sends, described DHCP request includes the MAC Address of described first terminal；From the Internet protocol IP address pool of described AP, described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And in the terminal association information table of described AP, record the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is original user, and User Status is not for switch state.

Further, processor 100, it is additionally operable to: after distributing an IP address for described first terminal, according to the terminal association information table that described first terminal is corresponding, generate synchronizing information；

Further, described wireless communication port 101, it is additionally operable to: described synchronizing information is sent to described controller, notify the described controller mark according to terminal association information table corresponding to described first terminal and described AP, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described AP, and current AP is designated the mark of described AP.

Further, described wireless communication port 101, it is additionally operable to: corresponding for described first terminal terminal association information table is sent to after described controller, receives the terminal that described controller sends and roll off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；

Further, described processor 100, it is additionally operable to: rolling off the production line notice according to described terminal, deleting terminal iidentification in described terminal association information table is the terminal association information table of the MAC Address of described first terminal, and discharges the described IP address distributing to described first terminal.

Described memorizer 102, is additionally operable to store described terminal association information table.

Above-mentioned processor 100 can be general processor, including CPU, NP etc.；Can also is that DSP, ASIC, FPGA or other PLDs, discrete gate or transistor logic, discrete hardware components.

In the present embodiment, do not use up details about the function of described AP and operation principle, be referred to described in the embodiment of the method for above-mentioned Fig. 2～5.

Based on technique scheme, consulting shown in Figure 11, the embodiment of the present invention also provides for a kind of AP, including processor 110, wireless communication port 111, memorizer 112, and bus 113, wherein:

Processor 110, wireless communication port 111, memorizer 112 is connected with each other by bus 113；Bus 113 can be pci bus or eisa bus etc..Described bus can be divided into address bus, data/address bus, control bus etc..For ease of representing, Figure 11 only represents with a thick line, it is not intended that only have a bus or a type of bus.

Memorizer 112, is used for depositing program.Specifically, program can include program code, and described program code includes computer-managed instruction.Memorizer 112 is likely to comprise RAM, it is also possible to also include nonvolatile memory, for instance at least one disk memory.

Wireless communication port 111, for receiving the association request that first terminal sends, described association request includes association request type；

Processor 110, for the program deposited in run memory 112, performs following operation:

When judging described association request type as re-association, generating user state information inquiry request, described user state information inquiry request includes the MAC Address of described first terminal.

Wireless communication port 111, for sending described user state information inquiry request to controller, so that described controller indicates whether to allow described first terminal to switch to described AP according to the MAC Address of described first terminal；

Wireless communication port 111, is additionally operable to receive the inquiry response that described controller sends, and described inquiry response includes switching instruction；

Processor 110, is additionally operable to when the switching in described inquiry response is designated as permission switching, it is allowed to described first terminal is associated with described AP；And in the terminal association information table of described AP, record the terminal association information table that described first terminal is corresponding；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer.

Further, processor 110, it is additionally operable to: when detecting that described first terminal is not in connection status, generates the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；

Further, wireless communication port 111, it is additionally operable to: send the request of described terminal management table entry deletion to described controller, notifies that the terminal management list item that described first terminal is corresponding deleted by described controller；And from the terminal association information table of described AP, delete the terminal association information table that described first terminal is corresponding.

Described memorizer 112, is additionally operable to store described terminal association information table.

Above-mentioned processor 110 can be general processor, including CPU, NP etc.；Can also is that DSP, ASIC, FPGA or other PLDs, discrete gate or transistor logic, discrete hardware components.

In sum, in the embodiment of the present invention, controller receives the purpose AP user state information sent inquiry；Medium education according to first terminal and the terminal management table of controller, obtain current AP mark corresponding to the first terminal identification request as the source AP of first terminal；User Status corresponding for first terminal in the terminal association information table of source AP is updated to handed over state by notice source AP, and current AP mark corresponding for first terminal in the terminal management table of controller is updated to the mark of purpose AP；Inquiry response is sent to purpose AP, this inquiry response includes allowing switching instruction, this permission switching instruction allows first terminal to be associated with purpose AP for indicative purpose AP, and records the terminal association information that first terminal is corresponding in the terminal association information table of purpose AP.Adopting technical solution of the present invention, when switching between different AP due to terminal, IP address remains unchanged, and solves in the process that terminal switches between different AP, it is impossible to ensure the problem that data service even causes service disconnection.Thus improve terminal to carry out the efficiency of AP switching, effectively prevent the interruption of data service, improve wireless communication quality.

Those skilled in the art are it should be appreciated that embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt the form of complete hardware embodiment, complete software implementation or the embodiment in conjunction with software and hardware aspect.And, the present invention can adopt the form at one or more upper computer programs implemented of computer-usable storage medium (including but not limited to disk memory, CD-ROM, optical memory etc.) wherein including computer usable program code.

The present invention is that flow chart and/or block diagram with reference to method according to embodiments of the present invention, equipment (system) and computer program describe.It should be understood that can by the combination of the flow process in each flow process in computer program instructions flowchart and/or block diagram and/or square frame and flow chart and/or block diagram and/or square frame.These computer program instructions can be provided to produce a machine to the processor of general purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device so that the instruction performed by the processor of computer or other programmable data processing device is produced for realizing the device of function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

These computer program instructions may be alternatively stored in and can guide in the computer-readable memory that computer or other programmable data processing device work in a specific way, the instruction making to be stored in this computer-readable memory produces to include the manufacture of command device, and this command device realizes the function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

These computer program instructions also can be loaded in computer or other programmable data processing device, make on computer or other programmable devices, to perform sequence of operations step to produce computer implemented process, thus the instruction performed on computer or other programmable devices provides for realizing the step of function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

Although preferred embodiments of the present invention have been described, but those skilled in the art are once know basic creative concept, then these embodiments can be made other change and amendment.So, claims are intended to be construed to include preferred embodiment and fall into all changes and the amendment of the scope of the invention.

Obviously, the embodiment of the present invention can be carried out various change and the modification scope without deviating from the embodiment of the present invention by those skilled in the art.So, if these amendments of the embodiment of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

Claims

1. the method that a terminal switches between access point AP, it is characterised in that including:

Controller receives the purpose AP user state information inquiry request sent, and described user state information inquiry request includes the MAC address of first terminal；

The terminal management table of the described controller MAC Address according to described first terminal and described controller, obtains current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；

Described controller notifies that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP, and current AP mark corresponding for first terminal described in the terminal management table of described controller is updated to the mark of described purpose AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；

Described controller sends inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

2. the method for claim 1, it is characterised in that before described controller receives the described purpose AP user state information inquiry request sent, described method also includes:

Controller receives the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；

Controller is according to the mark of described source AP and described synchronizing information, the terminal management table of described controller increases the terminal management list item that described first terminal is corresponding, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

3. method as claimed in claim 1 or 2, it is characterised in that described method also includes:

Described controller receives the terminal management table entry deletion request of described purpose AP, and the request of described terminal management table entry deletion includes the MAC Address of described first terminal；

MAC Address according to described first terminal and the terminal management table of described controller, described controller obtains the current AP mark that the MAC Address of described first terminal is corresponding；

If described current AP mark is identical with the mark of described purpose AP, host AP mark in the terminal management list item that then MAC Address of the described first terminal of described controller acquisition is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；

The terminal management list item of the MAC Address that terminal iidentification is described first terminal deleted by described controller from terminal management table.

4. the method that a terminal switches between access point AP, it is characterised in that including:

Source AP receives the switching notice that controller sends, and described switching notice includes the MAC address of first terminal；

Described source AP, according to described switching notice, obtains the terminal association information table that first terminal described in the terminal association information table of described source AP is corresponding, and the User Status in terminal association information table corresponding for described first terminal is updated to handed over state；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status.

5. method as claimed in claim 4, it is characterised in that before source AP receives the switching notice that controller sends, described method also includes:

Described source AP receives the association request that described first terminal sends, and described association request includes association request type；

When described source AP determines described association request type for associating first, described first terminal is carried out authenticating user identification；

After described authenticating user identification passes through, described source AP receives the dynamic host configuration protocol DHCP request that described first terminal sends, and described DHCP request includes the MAC Address of described first terminal；

Described source AP is from the Internet protocol IP address pool of described source AP, and described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And

In the terminal association information table of described source AP, recording the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, user type is original user, and User Status is not for switch state.

6. method as claimed in claim 5, it is characterised in that described source AP is that after described first terminal distribution the oneth IP address, described method also includes:

Described source AP, according to terminal association information table corresponding to described first terminal, generates synchronizing information；

Described synchronizing information is sent to described controller by described source AP, notify the described controller mark according to terminal association information table corresponding to described first terminal and described source AP, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

7. method as claimed in claim 6, it is characterised in that after described source AP is by terminal association information table transmission corresponding for described first terminal to described controller, described method also includes:

Described source AP receives the terminal that described controller sends and rolls off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；

It is the terminal association information table of the MAC Address of described first terminal that described source AP deletes terminal iidentification in described terminal association information table, and discharges the described IP address distributing to described first terminal.

8. the method as described in any one of claim 5 to 7, it is characterised in that before described source AP receives the association request that first terminal sends, described method also includes:

Described source AP receives the IP address information that described controller is described source AP distribution；Or, it is pre-configured with the IP address information of described source AP；Described IP address information includes the IP address pool of described source AP, subnet mask and gateway address.

9. the method that a terminal switches between access point AP, it is characterised in that including:

Purpose AP receives the association request that first terminal sends, and described association request includes association request type；

When described purpose AP judges described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the MAC address of described first terminal, so that described controller determines whether that described first terminal switches to described purpose AP；

Described purpose AP receives the inquiry response that described controller sends, and described inquiry response includes switching instruction；

If described switching is designated as permission switching, described purpose AP allows described first terminal to be associated with described purpose AP, and records the terminal association information table that described first terminal is corresponding in the terminal association information table of described purpose AP；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer.

10. method as claimed in claim 9, it is characterised in that after described purpose AP allows described first terminal to be switched to described purpose AP by described source AP, described method also includes:

When described purpose AP detects that described first terminal is not in connection status, generating the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；And

Send the request of described terminal management table entry deletion to described controller, notify that the terminal management list item that described first terminal is corresponding deleted by described controller；

Described purpose AP deletes the terminal association information table that described first terminal is corresponding from the terminal association information table of described purpose AP.

11. a switching control, it is characterised in that including:

Receiving unit, for receiving the purpose AP user state information inquiry request sent, described user state information inquiry request includes the MAC address of first terminal；

Acquiring unit, for the MAC Address according to described first terminal and terminal management table, obtains current AP mark corresponding to the described first terminal mark as the source AP of described first terminal；Described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；

Notification unit, for notifying that User Status corresponding for first terminal described in the terminal association information table of described source AP is updated to handed over state by described source AP；

Updating block, for being updated to the mark of described purpose AP by current AP mark corresponding for first terminal described in terminal management table；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；

Transmitting element, for sending inquiry response to described purpose AP, described inquiry response includes switching instruction, described switching is designated as permission switching, for indicating described purpose AP to allow described first terminal to be associated with described purpose AP, and in the terminal association information table of described purpose AP, record the terminal association information table that described first terminal is corresponding；Wherein, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and user type is roamer.

12. device as claimed in claim 11, it is characterised in that also including terminal management information increases unit, is used for:

Before receiving the described purpose AP user state information inquiry request sent, receive the described source AP synchronizing information sent；Wherein, described synchronizing information includes the terminal association information table that first terminal is corresponding；Mark according to described source AP and described synchronizing information, described terminal management table increases the terminal management list item that described first terminal is corresponding, in the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, host AP is designated the mark of described source AP, and current AP is designated the mark of described source AP.

13. the device as described in claim 11 or 12, it is characterised in that also include terminal management information deletion unit, be used for:

Receiving the terminal management table entry deletion request of described purpose AP, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；MAC Address according to described first terminal and described terminal management table, obtain the current AP mark that the MAC Address of described first terminal is corresponding；If described current AP mark is identical with the mark of described purpose AP, then obtain the host AP mark in the terminal management list item that the MAC Address of described first terminal is corresponding, notify that the AP of described host AP mark correspondence deletes the terminal association information table of the MAC Address that terminal iidentification is described first terminal, and discharge the Internet protocol IP address distributing to described first terminal；The terminal management list item of the MAC Address that terminal iidentification is described first terminal is deleted from terminal management table.

14. an access device, it is characterised in that including:

Receiving unit, for receiving the switching notice that controller sends, described switching notice includes the MAC address of first terminal；

Acquiring unit, for according to described switching notice, obtaining the corresponding terminal association information table of first terminal described in the terminal association information table of described access device；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；

Updating block, is updated to handed over state for the User Status in the terminal association information table that the first terminal that got by described acquiring unit is corresponding.

15. device as claimed in claim 14, it is characterised in that also include processing unit, be used for:

Before receiving the switching notice that controller sends, receiving the association request that described first terminal sends, described association request includes association request type；When determining described association request type for associating first, described first terminal is carried out authenticating user identification；After described authenticating user identification passes through, receiving the dynamic host configuration protocol DHCP request that described first terminal sends, described DHCP request includes the MAC Address of described first terminal；From the Internet protocol IP address pool of described access device, described first terminal is distributed in the selected IP address being in unallocated state, and is set to distribute state by the address state of a described IP address；And in the terminal association information table of described access device, record the terminal association information table that described first terminal is corresponding, in the terminal association information table that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, user type is original user, and User Status is not for switch state.

16. device as claimed in claim 15, it is characterised in that also include transmitting element, be used for:

After distributing an IP address for described first terminal, according to the terminal association information table that described first terminal is corresponding, generate synchronizing information；Described synchronizing information is sent to described controller, notify the described controller mark according to terminal association information table corresponding to described first terminal and described access device, terminal management table in the controller records the terminal management list item that described first terminal is corresponding；Wherein, described terminal management table is used for recording terminal iidentification, the corresponding relation of host AP mark and current AP mark；In the terminal management list item that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and host AP is designated the mark of described access device, and current AP is designated the mark of described access device.

17. device as claimed in claim 16, it is characterised in that also include terminal and roll off the production line processing unit, be used for:

Corresponding for described first terminal terminal association information table is sent to after described controller, receive the terminal that described controller sends and roll off the production line notice；Wherein, described terminal rolls off the production line and notifies to include the MAC Address of described first terminal；Deleting terminal iidentification in described terminal association information table is the terminal association information table of the MAC Address of described first terminal, and discharges the described IP address distributing to described first terminal.

18. the device as described in any one of claim 15 to 17, it is characterised in that also include IP address information acquiring unit, be used for:

Before receiving the association request that first terminal sends, receive the IP address information that described controller is the distribution of described access device；Or, it is pre-configured with the IP address information of described access device；Described IP address information includes the IP address pool of access device, subnet mask and gateway address.

19. an access device, it is characterised in that including:

Receiving unit, for receiving the association request that first terminal sends, described association request includes association request type；

Transmitting element, for when judging described association request type as re-association, generate user state information inquiry request to send to controller, described user state information inquiry request includes the MAC address of described first terminal, so that described controller determines whether that described first terminal switches to described access device；

Described reception unit, is additionally operable to receive the inquiry response that described controller sends, and described inquiry response includes switching instruction；

Switch unit, for when described switching is designated as permission switching, it is allowed to described first terminal is associated with described access device；And in the terminal association information table of described access device, record the terminal association information table that described first terminal is corresponding；Wherein, described terminal association information table is used for recording terminal iidentification, user type, the corresponding relation between User Status；In the terminal association information that described first terminal is corresponding, terminal iidentification is the MAC Address of described first terminal, and described user type is roamer.

20. device as claimed in claim 19, it is characterised in that also include terminal and roll off the production line processing unit, be used for:

When detecting that described first terminal is not in connection status, generating the request of terminal management table entry deletion, the request of described terminal management table entry deletion includes the MAC Address of described first terminal；And send the request of described terminal management table entry deletion to described controller, notify that the terminal management list item that described first terminal is corresponding deleted by described controller；The terminal association information table that described first terminal is corresponding is deleted from the terminal association information table of described access device.