CN101282304B

CN101282304B - Method for balancing load between access points, system, access point and mobile terminal

Info

Publication number: CN101282304B
Application number: CN2008101123554A
Authority: CN
Inventors: 徐百忱
Original assignee: Hangzhou H3C Technologies Co Ltd
Current assignee: New H3C Technologies Co Ltd
Priority date: 2008-05-22
Filing date: 2008-05-22
Publication date: 2011-09-28
Anticipated expiration: 2028-05-22
Also published as: CN101282304A

Abstract

The invention provides a method for achieving the load symmetry between the accessing point (AP), a system, AP and moving terminal (STA), which is applied to the radio network. The radio network comprises at least two load symmetry server sets (LSS) composed by the AP. The method comprises: while the AP receives the LSS message sent by the STA, processing the selection in the AP which the STA can be accessed according to the load situation of each AP in the LSS noticing the STA to access the selected AP; so that the invention can enhance the load symmetry effect among the AP.

Description

Realize method, system, access point and the portable terminal of load balancing between access point

Technical field

The present invention relates to the mobile communication technology field, particularly a kind of method, system, AP and portable terminal (STA) of realizing inserting load balancing between (AP).

Background technology

The service that each AP provides for the user in the wireless lan (wlan) can adopt service set (ESSID) to identify usually, and a plurality of AP can use common ESSID, and as shown in Figure 1, the network that adopts same ESSID is extended service set (ESS); Each AP among the same ESS adopts basic service set identification (BSSID) to distinguish, the corresponding AP of BSSID, and the network that adopts same BSSID is Basic Service Set (BSS).

The process of each STA access AP mainly comprises in the prior art: STA at first carries out the scanning to AP, and the AP that STA scans is the current AP that can insert of this STA; One of them AP of surface sweeping policy selection that the STA basis is preset, and to the AP of this selection transmission access request, for example, STA can select the AP that signal strength signal intensity is a strongest transmission access to ask in the AP that scans; After this AP receives the access request of this STA,,, then allow the access of this STA,, then refuse the access of this STA if the load state of self has reached the load upper limit if the load state of self does not reach the load upper limit according to the load state of self.

Said method of the prior art is STA for the right to choose that inserts AP, promptly initiatively select the AP that inserts by STA, usually that default load balancing strategy is normally selected the signal strength signal intensity maximum or select any one etc., be difficult to realize select to insert according to the load state of AP; Even if AP can allow according to the load state of self or the access of refusal STA, but because the load balancing strategy of STA end is predefined, this will cause STA to continue to attempt inserting this AP according to this load balancing strategy, and this AP continues the access of this STA of refusal.So, this method load balancing poor effect of the prior art.

Summary of the invention

In view of this, the invention provides method, system, AP and the STA of load balancing between a kind of AP of realization, so that improve the load balancing effect between AP.

A kind of method that realizes load balancing between access point AP is applied in the wireless network, and this wireless network comprises the LSS that at least two AP form; This method comprises:

Each AP in the described wireless network gives STA by probe response Probe Response or beacon frame with self basic service set identification BSSID and the LSS identification of broadcast under self, select a LSS for STA according to the LSS sign that gets access to, in the AP that scans, select an AP who belongs to described LSS, send the LSS message to the AP of this selection;

Receive the AP of described LSS message, determine the AP that this STA can insert according to the information of carrying in this LSS message;

The described load state that receives the AP of LSS message according to each AP among the LSS under self is selected in the AP that described STA can insert according to predefined load balancing strategy, notifies described STA to insert the AP that selects.

A kind of method that realizes load balancing between AP, this method comprises:

STA scans each AP, is specially: broadcast probe request Probe Request, obtain the BSSID of each AP self that each AP sends by Probe Response or beacon frame and affiliated LSS sign;

Described STA selects a LSS according to the LSS sign that gets access to, and selects an AP who belongs to described LSS as master control AP in the AP that scans;

Described STA sends the LSS message that comprises the AP information that this STA can insert to described master control AP, is that described STA select an AP as insert AP according to described information in conjunction with predefined load balancing strategy for this master control AP;

When receiving the notice of the access AP that access that described master control AP sends selects, attempt inserting described access AP.

A kind of AP, this AP comprises: packet sending unit, message receiving element, first selected cell and first notification unit;

Described packet sending unit, be used for giving STA with BSSID and the LSS identification of broadcast under this AP of this AP by Probe Response or beacon frame, select a LSS for STA according to the LSS sign that gets access to, in the AP that scans, select an AP who belongs to described LSS, send the LSS message to the AP of this selection;

Described message receiving element is used to receive the LSS message that STA sends;

Described first selected cell, be used for when described message receiving element receives described LSS message, determine the AP that this STA can insert according to the information of carrying in this LSS message, according to the load state of each AP among the LSS under this AP, in the AP that described STA can insert, select according to predefined load balancing strategy;

Described first notification unit is used to notify described STA to insert the AP that described first selected cell is selected.

A kind of STA, this STA comprises: scanning element, LSS selected cell, master control AP selected cell, packet sending unit, message receiving element and access unit;

Described scanning element is used for each AP is scanned, and obtains LSS sign and BSSID that the AP that scans passes through Probe Response or beacon frame transmission;

Described LSS selected cell, the LSS sign that is used for getting access to according to described scanning element is selected a LSS;

Described master control AP selected cell is used for the AP that scans in described scanning element, selects an AP who belongs to the LSS that described LSS selected cell selects as master control AP;

Described packet sending unit is used for sending the LSS message that comprises the AP information that this STA can insert to described master control AP;

Described message receiving element is used to receive the notice of the access AP that access that described master control AP sends selects;

Described access unit is used for according to described notice, attempts inserting described access AP.

As can be seen from the above technical solutions, be mainly used in the wireless network in the present invention, this wireless network comprises the LSS that at least two AP form, and when AP receives the LSS message of STA transmission, determines the AP that this STA can insert according to the information of carrying in this LSS message; According to the load state of each AP among the LSS under self, select in the AP that this STA can insert according to predefined load balancing strategy, notify this STA to insert the AP that selects.Be which AP the present invention only inserts by the STA decision, but by the AP of network terminal load state according to each AP among the LSS under self, from the AP that STA can insert, specify an AP to insert for STA, considered the load state of the AP that STA can insert, for example, can specify STA to insert load AP less or that surplus resources is more, thereby improve the load balancing effect between AP.

Description of drawings

Fig. 1 is the corresponding relation schematic diagram of ESS and BSS in the local area network (LAN);

The method flow diagram that Fig. 2 provides for the embodiment of the invention;

The BSSID list structure figure that Fig. 3 provides for the embodiment of the invention;

The example flow chart that Fig. 4 provides for the embodiment of the invention;

Fig. 5 initiatively upgrades flow chart for what the embodiment of the invention provided;

The passive renewal flow chart that Fig. 6 provides for the embodiment of the invention;

The heavy allocation flow figure that Fig. 7 provides for the embodiment of the invention;

The system construction drawing that Fig. 8 provides for the embodiment of the invention.

Embodiment

In order to make the purpose, technical solutions and advantages of the present invention clearer, describe the present invention below in conjunction with the drawings and specific embodiments.

Method provided by the invention mainly comprises: the AP of fellowship load balancing is set to a load balancing service collection (LSS) in advance, when the AP among this LSS receives the LSS message of STA, determine the AP that this STA can insert according to the information of carrying in this LSS message, load state according to each AP among this LSS, select in the AP that this STA can insert according to predefined load balancing strategy, notify this STA to insert the AP of this selection.

Wherein, above-mentioned LSS message can be that LSS inserts request, promptly carries out said method when the STA request inserts AP and realizes load balancing; Above-mentioned LSS message also can be other LSS message, for example: the LSS report message, promptly STA is after inserting AP, and the AP of current access realizes load balancing according to the load balancing situation thereby specify this STA to insert another AP.

Below said method is described in detail, the method flow diagram that Fig. 2 provides for the embodiment of the invention, as shown in Figure 2, this method can may further comprise the steps:

Step 201: the AP with the fellowship load balancing is set at a LSS in advance.

Can there be a LSS among the ESS, also can has a plurality of LSS.For example, all AP or a part of AP fellowship load balancing among ESS, then the AP with this fellowship load balancing is set at a LSS, adopts common LSS ID to identify; Has wherein a part of AP fellowship load balancing among the ESS, some AP fellowship load balancing in addition, still, these two parts carry out load balancing respectively, then can be set to two LSS by these two parts, adopt different LSS ID to identify respectively.

Step 202:STA scans AP.

In this step, STA can have two kinds of forms in the process that AP is scanned, a kind of is active scan, i.e. STA active broadcast probe requests thereby (Probe Request), and the AP that receives this Probe Request message replys probe response (Probe Response) to this STA; Another kind is a drive sweep, and promptly STA monitors the beacon frame (Beacon) that AP sends.Each AP carries BSSID and the LSS ID of self in Probe Response that sends or Beacon, the AP that does not participate in load balancing can not comprise LSS ID, and perhaps this LSS ID is set to 0.This step shown in Fig. 2 adopts the mode of active scan.

Carried the BSSID of AP self among Probe Response of the prior art or the Beacon, in addition, can adopt in Probe Response or Beacon field of expansion to carry LSS ID under the AP, the length of this extended field can set in advance according to the actual requirements, for example, the length of 2 bytes can be set, span is 1 to 65535, in addition, can adopt value 0 this AP of sign not participate in load balancing.

Step 203:STA selects a LSS according to the LSS ID of the AP that scans, and selects an AP as master control AP in this LSS, sends LSS to this AP and inserts request (LSS Request).

In this step, if only there is a LSS among the AP that STA scans, then this STA selects this LSS; If the AP that scans belongs to different LSS, then STA can select wherein any one LSS; If the AP that scans does not belong to any one LSS, then STA selects any one AP to attempt inserting, and promptly sends the request of access.

The selection mode of master control AP can have multiple mode in addition, for example, can select an AP among this LSS as master control AP arbitrarily, the AP that also can select signal strength signal intensity maximum among this LSS is as master control AP, also can select the best AP of channel quality among this LSS as master control AP etc., not limit at this selection mode to master control AP.

STA can be included in the BSSID tabulation of BSSID formation that belongs to the AP of this LSS among the AP that scans and send to this master control AP among the LSS Request.Wherein, the form of BSSID tabulation can adopt structure shown in Figure 3, each BSSID information in this BSSID tabulation can take 2 bytes, comprise in each BSSID information and comprise BSSID at least, BSSID adopts the form sign of the MAC Address of AP in the drawings, in addition, can also comprise the signal strength signal intensity, channel information of this AP that STA receives etc. in each BSSID information, this signal strength signal intensity, channel information also can be used as the Consideration of master control AP when specifying an AP.For example, master control AP can select the AP of signal quality greater than setting threshold from the BSSID tabulation, in the AP of the signal quality of selecting greater than setting threshold, further select again according to predefined load balancing strategy, select the best AP of load state, so just can guarantee that the AP that selects has more excellent signal quality, guarantee the quality of service of STA.

Step 204: after master control AP receives LSS Request, load state according to other AP among this LSS that gets access in advance, select an AP the BSSID tabulation that is comprised from this LSS Request, the BSSID of this AP is carried at LSS inserts in the response (LSS Response) and send to STA.

Among the present invention, each AP that belongs among the same LSS can be by the periodically mutual self load condition of agreement between AP, and the load state of other AP stored, after master control AP receives LSS Request, can utilize the load state of each AP among this LSS that self stores, select an AP to insert for STA.

Wherein, the concrete load balancing strategy of AP does not limit, and for example, can select the AP of load minimum, can be from load state less than choosing one of them AP the AP of the load upper limit wantonly, can selecting the maximum AP of surplus resources etc. yet yet.In addition, when the load state of AP is more or less the same, also can be with the Consideration as selection such as the signal strength signal intensity of the AP that from BSSID tabulation, obtains, channel information.

In addition, master control AP can also be according to the load state of each AP, and the AP of each the BSSID correspondence in the BSSID tabulation is carried out prioritization, and for example, the less AP priority of load is higher, and the result sends to STA with this prioritization.

Step 205: this STA judges setting in the time limit whether receive LSS Response, if then execution in step 206; Otherwise execution in step 207.

Step 206: this STA inserts process ends to the pairing AP of BSSID that carries among this LSS Response.

If that master control AP sends to STA is the prioritization result of each BSSID in the BSSID tabulation, then STA can be according to this prioritization result, at first select the highest AP of priority to attempt inserting, if attempt failure, the AP that then selects priority to take second place again attempts inserting.

Step 207:STA reselects BSSID deletion from the BSSID tabulation of this LSS of this master control AP a master control AP, and sends the LSS Request that comprises the BSSID tabulation of renewal back to this master control AP, goes to execution in step 204.

Suppose that STA scans three AP and belongs to same LSS, be AP 1, AP 2 and AP3, then the idiographic flow of this method can be as shown in Figure 4, be that STA knows that by scanning AP 1, AP 2 and AP3 belong to same LSS, this STA sets up the BSSID tabulation, comprises the BSSID of AP 1, AP 2 and AP3 in this BSSID tabulation.At this moment, STA selects the highest AP 2 of signal strength signal intensity as master control AP, sends the LSS Request that comprises the BSSID tabulation to AP 2; After AP 2 receives this LSS Request,, determine the load minimum of AP3 in this BSSID tabulation, then the BSSID of this AP 3 is included among the LSS Response and sends to STA according to the load state of each AP among this LSS of self storage; After STA receives LSS Response, send the request of access to AP 3, insert AP 3 according to the BSSID that wherein comprises.

After STA inserts AP, in order to guarantee and safeguard the visible relation between STA and the AP, make things convenient for AP that STA is reassigned access, need upgrade the LSS information that this STA can insert, this renewal process can have two kinds of forms:

A kind of form is initiatively to upgrade, and the AP of the current access of this STA can initiatively send LSS to this STA and upgrade message (LSS Update); This STA scans AP after receiving LSS Update again, obtains the BSSID of each AP that belongs to this LSS among the AP that scans and forms the BSSID tabulation, this BSSID tabulation is sent to the AP of current access by LSS report message (LSS Report); If there is not to store BSSID tabulation among the current AP at this STA, then preserve this BSSID tabulation, if stored BSSID tabulation among the current AP, then utilize this BSSID that obtains to tabulate the BSSID tabulation of self storage is upgraded at this STA.Wherein, this AP can periodically carry out active to be upgraded, and also can carry out active when situation that STA moves acquires a certain degree and upgrade perceiving, and carries out active renewal etc. in the time of also can changing at the state of AP self.Initiatively the flow process of upgrading can be as shown in Figure 5, and AP 3 is the AP of the current access of STA among Fig. 5.

Another kind of form is passive renewal, and STA scans each AP again, obtains the BSSID of each AP among this LSS that can insert and forms the BSSID tabulation, this BSSID tabulation is sent to the AP of current access by LSSReport; This LSS Report of reception that current AP is passive, and obtain the BSSID that comprises among this LSS Report and tabulate, if there be not the BSSID tabulation of storage among the current AP at this STA, then preserve this BSSID tabulation, if stored BSSID tabulation among the current AP, then utilize this BSSID tabulation of obtaining that the BSSID tabulation of self storing is upgraded at this STA.Wherein, STA can periodically send LSS Report, also can send LSS Report when self moving state acquires a certain degree, and sends LSS Report etc. when the signal strength signal intensity of the current AP that perhaps perceives is reduced to setting threshold.The flow process of passive renewal can be as shown in Figure 6, and AP 3 is the AP of the current access of STA among Fig. 6.

In addition, in some cases, for example the channel status of current AP changes, can't bear the STA quantity of the current access of this AP, perhaps, current AP need be restarted or maintenance etc., current AP need go to all or part of STA of current access and insert other AP, can realize by the heavy allocation flow of LSS this moment, the heavy allocation flow figure that Fig. 7 provides for the embodiment of the invention, in this embodiment, AP 3 is the AP of the current access of STA, supposes that AP 3 need be transferred to the STA of current access other AP.As shown in Figure 7, heavy assigning process can may further comprise the steps:

Step 701:AP 3 tabulates according to the BSSID at this STA of self storage, chooses the BSSID of an AP from this BSSID tabulation.

In this step, AP 3 can be according to the load state of each AP among self place LSS of self storage, from the BSSID tabulation of this STA of self storage, select the BSSID of an AP, certainly, AP 3 also can directly carry out above-mentioned more new technological process and obtain the tabulation at the BSSID of this STA, selects the BSSID of an AP from this BSSID tabulation of obtaining.Equally, can select the AP of load minimum, perhaps the maximum AP of surplus resources perhaps selects an AP etc. arbitrarily; Certainly, also can specify an AP in advance, select the strategy of AP not limit at this.

Step 702:AP 3 is carried at the heavy assignment message of LSS (LSS Reassign) with the BSSID of the AP that chooses and sends to this STA.

Step 703: after this STA receives LSS Reassign, insert the AP of the entrained BSSID correspondence of this LSS Reassign,, suppose that this AP is AP 2 at this.

LSS Update that adopts in the above-mentioned renewal process and LSS Report, and the LSS Reassign that adopts in the heavy assigning process can adopt the form of Action frame, can in the Frame of Action frame Body territory, carry, adopt the Action field field in the Frame Body territory to carry type of message information, its corresponding relation is as shown in table 1, when being 0, the value in the Action field field shows that this message is LSS Update, show that when the value in the Action field field is 1 this message is LSS Report, show that when the value in the Action field field is 2 this message is LSS Reassign; Carry BSSID in the information field in the Frame Body territory, perhaps information such as BSSID tabulation, for example, can carry the whether successful information of renewal in the information field of LSS Report correspondence and upgrade after the BSSID tabulation, can carry the BSSID or the BSSID tabulation of appointment in the information field of LSS Reassign correspondence.

Table 1

Action?Field	Corresponding type of message
		0	LSS?Update
1	LSS?Report
		2	LSS?Reassign
Other	Reserve

More than be description, below the system that the embodiment of the invention provided be described method provided by the present invention, the system construction drawing that Fig. 8 provides for the embodiment of the invention, as shown in Figure 8, this system mainly comprises: AP 800 and STA 810.

STA 810, are used for sending the LSS message to AP 800, after the notice of the AP that the access that reception AP 800 sends is selected, attempt inserting this AP that selects.

AP 800, when being used to receive the LSS message of STA 810 transmissions, determine the AP that this STA can insert according to the information of carrying in this LSS message, load state according to each AP among the LSS under self, select in the AP that STA 810 can insert according to predefined load balancing strategy, notify this STA 810 to insert the AP that selects.

Wherein, AP 800 can comprise: message receiving element 801, first selected cell 802 and first notification unit 803.

Message receiving element 801 is used to receive the LSS message that STA 810 sends.

First selected cell 802 is used for when message receiving element 801 receives the LSS message, according to the load state of each AP among the LSS of this AP, selects in the AP that STA 810 can insert.

First notification unit 803 is used to notify STA 810 to insert the AP that first selected cell 802 is selected.

This AP can also comprise: packet sending unit 804, be used for by beacon frame with self BSSID and self under LSS ID be broadcast to STA 810.

Also can adopt another mode to broadcast self BSSID and self described LSS ID, at this moment:

Message receiving element 801 can also be used to receive the Probe Request that STA 810 sends.

Packet sending unit 804 is used for when message receiving element 801 receives Probe Request, by Probe Response with self BSSID and self under LSS ID send to STA 810.

Wherein, above-mentioned first selected cell 802 can comprise: load state obtains subelement 8021, subelement 8022 and chooser unit 8023 are obtained in tabulation.

Load state obtains subelement 8021, be used for by agreement between AP periodically with this AP 800 under the mutual load state of other each AP of LSS.

Subelement 8022 is obtained in tabulation, is used for inserting request from LSS and obtains the BSSID tabulation, the AP that the pairing AP of each BSSID can insert as STA 810 during this BSSID was tabulated.

Chooser unit 8023 is used for obtaining according to load state the load state of each AP that subelement 8032 obtains, according to default load balancing strategy, selects one or more AP from the BSSID tabulation.

At this moment, first notification unit 803 can comprise: information carries subelement 8031 and information sends subelement 8032.

Information is carried subelement 8031, and the BSSID that is used for a AP that chooser unit 8023 is selected is carried at LSS Response, and perhaps the ranking results that carries out after the prioritization of a plurality of AP that chooser unit 8023 is selected is carried among the LSS Response.

Information sends subelement 8032, is used to send LSS Response.

The structure of above-mentioned AP is the structure of this AP during as master control AP, because an AP also may be as the AP of the current access of other STA in as master control AP in network, the STA that supposes current this AP of access is STA 820.At this moment, as the AP of current access, it can have following structure:

This AP can also comprise: tabulation acquiring unit 805.

Message receiving element 801 can also be used to receive the LSS report message that the STA 820 that inserts this AP sends.

Tabulation acquiring unit 805 also is used for the report message from LSS, obtains the tabulation at the BSSID after the renewal of the STA820 that inserts this AP.

Wherein, above-mentioned LSS report message can be set out to send when satisfying update condition at STA 820, also can be this AP after this STA 820 sends LSS and upgrades messages, and STA 820 replys to this AP 800.

This AP can also comprise: second selected cell 806 and second notification unit 807.

Second selected cell 806 is used for the load state according to each AP of LSS under self, selects the BSSID of another AP from the BSSID tabulation after the renewal that tabulation acquiring unit 805 obtains.

Second notification unit 807 is used for that the BSSID that second selected cell 806 is selected is carried at the heavy assignment message of LSS and sends to the STA 820 that inserts this AP, inserts the AP of the BSSID correspondence of selecting with the STA 820 of this AP of notice access.

Correspondingly, STA 810 can comprise: packet sending unit 811, message receiving element 812 and access unit 813.

Packet sending unit 811 is used for sending the LSS message that comprises the AP information that this STA can insert to AP 800.

Message receiving element 812 is used to receive the notice of the AP that access that AP sends selects.

Access unit 813 is used for according to above-mentioned notice, attempts inserting the AP that selects.

This STA 810 can also comprise: scanning element 814, LSS selected cell 815 and master control AP selected cell 816.

Scanning element 814 is used for each AP is scanned, and obtains LSS ID and BSSID that the AP that scans passes through Probe Response or beacon frame transmission.

LSS selected cell 815, the LSS ID that is used for getting access to according to scanning element 814 selects a LSS.

Master control AP selected cell 816 is used for the AP that scans in scanning element 814, selects an AP who belongs to the LSS that LSS selected cell 815 selects as master control AP.This master control AP is AP 800.

Packet sending unit 811 sends the LSS message to master control AP 800.

This STA can also comprise: the pairing BSSID of AP that tabulation processing unit 817, the AP that is used for utilizing scanning element 814 to scan belong to the LSS of selection forms the BSSID tabulation, and this BSSID tabulation is carried in the LSS message.

This STA can also comprise: timer 818 is used for picking up counting when packet sending unit 811 sends the LSS message.

Tabulation processing unit 817, prescribe a time limit when the timing time of timer 818 reaches setting if also be used for, message receiving element 812 does not still receive the notice that master control AP 800 sends, then the BSSID with master control AP 800 deletes from the BSSID tabulation, and sends the gravity treatments notice to master control AP selected cell 816.

Master control AP selected cell 816, also be used to receive gravity treatment notice after, in the AP that scans, select another AP that belongs to LSS as master control AP again, and trigger packet sending unit 811 and send the LSS message to this master control AP that reselects.

In addition, realize the BSSID list update if desired, this STA 810 can also comprise: upgrade trigger element 819.

Message receiving element 812 also is used to receive the LSS that the AP of these STA 810 current accesses sends and upgrades message.

Upgrade trigger element 819, be used for receiving LSS when upgrading message satisfying the update condition set or message receiving element 812, driver sweep unit 814 scans each AP again.

Tabulation processing unit 817 also is used to utilize the result that scanning element 814 scans each AP again to upgrade the BSSID tabulation, and the tabulation of the BSSID after will upgrading is carried in the LSS report message.

Packet sending unit 811 also is used for the LSS report message is sent to the AP of the current access of this STA.

Realize heavy assigning process if desired, then the message receiving element 812, also are used to receive the heavy assignment message that the AP of the current access of this STA sends.

Access unit 813 also is used for rolling off the production line from the AP of current access, attempts inserting the AP of the entrained BSSID correspondence of heavy assignment message.

By above description as can be seen, be mainly used in the wireless network in the present invention, this wireless network comprises the LSS that at least two AP form, and when AP receives the LSS message of STA transmission, determines the AP that this STA can insert according to the information of carrying in this LSS message; According to the load state of each AP among the LSS under self, select in the AP that this STA can insert according to predefined load balancing strategy, notify this STA to insert the AP that selects.Be which AP the present invention only inserts by the STA decision, but by the AP of network terminal load state according to each AP among the LSS under self, from the AP that STA can insert, specify an AP to insert for STA, considered the load state of the AP that STA can insert, for example, can specify STA to insert load AP less or that surplus resources is more, thereby improve the load balancing effect between AP.

The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being made, is equal to replacement, improvement etc., all should be included within the scope of protection of the invention.

Claims

1. a method that realizes load balancing between access point AP is characterized in that, is applied in the wireless network, and this wireless network comprises the load balancing service collection LSS that at least two AP form; This method comprises:

Each AP in the described wireless network gives portable terminal STA by probe response Probe Response or beacon frame with self basic service set identification BSSID and the LSS identification of broadcast under self, select a LSS for STA according to the LSS sign that gets access to, in the AP that scans, select an AP who belongs to described LSS, send the LSS message to the AP of this selection;

The AP that receives described LSS message determines the AP that this STA can insert according to the information of carrying in this LSS message;

2. method according to claim 1 is characterized in that, the information of carrying in the described LSS message is: BSSID tabulation, this BSSID tabulation comprise the pairing BSSID of AP that belongs to the LSS of described selection among the AP that described STA scans;

The AP that described STA can insert is the pairing AP of BSSID that comprises in the described BSSID tabulation.

3. method according to claim 2 is characterized in that, the information of carrying in the described LSS message also comprises: the signal quality information of AP that belongs to the LSS of described selection among the AP that described STA scans;

Be chosen as in the AP that described STA can insert according to predefined load balancing strategy: in the AP that described STA can insert, select the AP of signal quality greater than setting threshold, in the AP of the signal quality of selecting, select according to predefined load balancing strategy greater than setting threshold.

4. according to the described method of the arbitrary claim of claim 1 to 3, it is characterized in that this method also comprises: each AP that belongs to same LSS passes through the periodically mutual self load condition of agreement between AP, and the load state of each AP among this LSS is stored;

Load state according to each AP among the LSS under self, according to default load balancing strategy, select to be specially in the AP that described STA can insert: the AP of the described LSS of receiving message selects one or more AP according to the load state of each AP that self stores according to default load balancing strategy in the AP that STA can insert.

5. method according to claim 4, it is characterized in that, notifying described STA to insert the AP that selects is specially: the BSSID of an AP of described selection is carried at the load balancing service collection inserts among the response LSS Response and send to described STA, attempt inserting the pairing AP of BSSID that described LSS Response carries for described STA; Perhaps,

The described a plurality of AP that select are carried out prioritization, this prioritization result is carried at sends to described STA among the LSSResponse, attempt inserting described a plurality of AP for described STA one by one according to described prioritization result, until inserting successfully.

6. a method that realizes load balancing between access point AP is characterized in that, this method comprises:

Portable terminal STA scans each AP, be specially: broadcast probe request Probe Request, obtain the basic service set identification BSSID of each AP self that each AP sends by probe response Probe Response or beacon frame and affiliated load balancing service collection LSS sign;

7. method according to claim 6 is characterized in that, the AP information that described STA can insert is: BSSID tabulation, this BSSID tabulation comprise the pairing BSSID of AP that belongs to the LSS of selection among the AP that described STA scans.

8. method according to claim 7, it is characterized in that, this method also comprises: if described STA is setting the notice that does not receive the access AP that inserts selection in the time limit, then the BSSID with described master control AP deletes from described BSSID tabulation, and in the AP that scans, select another AP that belongs to described LSS again, and go to execution sends step from the LSS message to master control AP as master control AP.

9. method according to claim 6, it is characterized in that, described STA also comprises after inserting described access AP: when satisfying the update condition of setting, described STA scans each AP again, according to scanning result described BSSID tabulation is upgraded, and the tabulation of the BSSID after will upgrading sends to the AP of the current access of this STA by the LSS report message; Perhaps,

Described STA receives after LSS that the AP of current access sends upgrades message, again each AP is scanned, according to scanning result described BSSID tabulation is upgraded, and the tabulation of the BSSID after will upgrading sends to the AP of the current access of described STA by the LSS report message.

10. an access point AP is characterized in that, this AP comprises: packet sending unit, message receiving element, first selected cell and first notification unit; Described packet sending unit with link to each other with described message receiving element, described message receiving element links to each other with described first selected cell, described first selected cell links to each other with described first notification unit;

Described packet sending unit, be used for giving portable terminal STA with basic service set identification BSSID and the load balancing service collection LSS identification of broadcast under this AP of this AP by probe response Probe Response or beacon frame, select a LSS for STA according to the LSS sign that gets access to, in the AP that scans, select an AP who belongs to described LSS, send the LSS message to the AP of this selection;

11. AP according to claim 10 is characterized in that, described first selected cell comprises:

Load state obtains subelement, be used for by agreement between AP periodically with this AP under the mutual load state of other each AP of LSS;

Subelement is obtained in tabulation, is used for obtaining the BSSID tabulation from described LSS message the AP that the pairing AP of each BSSID can insert as described STA during this BSSID was tabulated;

The chooser unit is used for obtaining according to load state the load state of each AP that subelement obtains, according to default load balancing strategy, selects one or more AP from described BSSID tabulation;

Described first notification unit comprises: information carries subelement and information sends subelement;

Described information is carried subelement, the BSSID that is used for a AP that described chooser unit is selected is carried at the load balancing service collection and inserts response LSS Response, and perhaps the ranking results that carries out after the prioritization of a plurality of AP that described chooser unit is selected is carried among the LSS Response;

Described information sends subelement, is used to send described LSS Response.

12. AP according to claim 10 is characterized in that, this AP also comprises: the tabulation acquiring unit;

Described message receiving element also is used to receive the LSS report message that the STA that inserts this AP sends;

The tabulation acquiring unit also is used for from described LSS report message, obtains the tabulation at the BSSID after the renewal of the STA of described this AP of access.

13. AP according to claim 12 is characterized in that, this AP also comprises: second selected cell and second notification unit;

Described second selected cell is used for the load state according to each AP of LSS under self, selects the BSSID of another AP the BSSID tabulation after the renewal that described tabulation acquiring unit obtains;

Described second notification unit is used for the BSSID that described second selected cell is selected is carried at the STA that the heavy assignment message of LSS sends to described this AP of access, inserts the AP of the BSSID correspondence of described selection with the STA that notifies described this AP of access.

14. a portable terminal STA is characterized in that, this STA comprises: scanning element, load balancing service collection LSS selected cell, master control access point AP selected cell, packet sending unit, message receiving element and access unit;

Described scanning element is used for each AP is scanned, and obtains LSS sign and basic service set identification BSSID that the AP that scans sends by probe response Probe Response or beacon frame;

15. STA according to claim 14, it is characterized in that, this STA also comprises: the tabulation processing unit, the pairing BSSID of AP that the AP that is used for utilizing described scanning element to scan belongs to the LSS of described selection forms the BSSID tabulation, and this BSSID tabulation is carried in the described LSS message.

16. STA according to claim 15 is characterized in that, this STA also comprises: timer is used for picking up counting when described packet sending unit sends the LSS message;

Described tabulation processing unit, prescribe a time limit when the timing time of described timer reaches setting if also be used for, described message receiving element does not still receive the described notice that described master control AP sends, then the BSSID with described master control AP deletes from described BSSID tabulation, and sends the gravity treatment notice to described master control AP selected cell;

Described master control AP selected cell, also be used to receive described gravity treatment notice after, in the described AP that scans, select another AP that belongs to described LSS as master control AP again, and trigger described packet sending unit and send the LSS message to this master control AP that reselects.

17. STA according to claim 15 is characterized in that, this STA also comprises: upgrade trigger element;

Described message receiving element also is used to receive the LSS that the AP of the current access of this STA sends and upgrades message;

Described renewal trigger element is used for receiving LSS when upgrading message at the update condition of satisfy setting or described message receiving element, triggers described scanning element and again each AP is scanned;

Described tabulation processing unit also is used to utilize the result that described scanning element scans each AP again to upgrade described BSSID tabulation, and the tabulation of the BSSID after will upgrading is carried in the LSS report message;

Described packet sending unit also is used for described LSS report message is sent to the AP of the current access of this STA.

18. a system that realizes load balancing between AP is characterized in that, this system comprises described AP of claim 10 and the described STA of claim 14.