MX2008005720A - Method and system for autonomous channel coordination for a wireless distribution system - Google Patents

Abstract

A method and system for autonomous channel coordination for a wireless distribution system (WDS) are disclosed. A wireless communication system includes a plurality of access points (APs) and the APs communicate each other via a WDS. A coordinated channel group (CCG) of a plurality of member APs is established. The member APs of the CCG camp on a WDS channel used for the WDS among the member APs of the CCG. One AP among the member APs of the CCG is designated as a master AP. The master AP coordinates with other member APs of the CCG for selecting and configuring the WDS channel for the CCG and addition and deletion of member APs. By allowing APs to define a CCG, changes of the WDSchannel are performed autonomously while maintaining connectivity.

Description

METHOD AND SYSTEM FOR AUTONOMOUS CHANNEL COORDINATION FOR WIRELESS DISTRIBUTION SYSTEM FIELD OF THE INVENTION The present invention relates to wireless communication systems. More particularly, the present invention relates to a method and system for autonomous channel coordination for a wireless distribution system (WDS).

BACKGROUND In a WLAN system such as 802.11, stations (STA) within a basic service set (BSS) share the same frequency channel to communicate with each other. In an infrastructure mode BSS, an access point (AP) retransmits traffic to and from a distribution system (DS). Many BBSs can be connected to the DS through their APs. Communication between APs and other nodes within a DS can be supported by any medium access control (MAC) scheme such as IEEE 802.3 in the case where a wired infrastructure exists. If a wired infrastructure does not exist, communication between the APs can also be carried out wirelessly. A set of APs that communicate wirelessly constitutes a WDS.

For successful communication between two APs in a WDS, the sending AP must transmit a packet on the channel used by the receiving AP. Generally, APs may select the channel (i.e., the WDS channel) of a plurality of available channels to communicate with other APs. Typically, the WDS channel is the same as the BSS channel used by an AP to transmit and receive packets to and from the STA in its own BSS. In the prior art, the WDS channel is manually configured by a system administrator and the APs are not able to dynamically change the WDS channel autonomously. However, manual configuration and adjustment are problematic, susceptible to errors and costly. In addition, the most suitable WDS channel for communication within WDS changes dynamically on a short-term basis due to changes in interference and traffic conditions. It is not realistic to manually keep track of these changes and change the WDS channel. Therefore, it would be desirable to provide a method and system for autonomously configuring the WDS channel and at the same time maintaining connectivity within the WDS.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a method and system for autonomous channel coordination for a WDS. A wireless communication system includes a plurality of APs and the APs communicate with each other via the WDS. A coordinated channel group (CCG) comprising a plurality of AP members is established. The AP members of the CCG field in a WDS channel are used for WDS among the member APs of the CCG. An AP between AP members of the CCG is designated as the master AP. The master AP coordinates with other AP members of the CCG to select and configure the WDS channel for the CCG and the addition and deletion of the member APs. By allowing the APs to define a CCG, the WDS channel changes are made autonomously and at the same time the connectivity is maintained within the WDS.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows an exemplary wireless communication system with a WDS in which the present invention is implemented. Figure 2 is a signaling diagram of a process for exchanging messages to join a CCG between an AP and a master AP, according to the present invention. Figure 3 is a signaling diagram of a process for exchanging messages to leave a CCG between an AP and a master AP, in accordance with the present invention. Figure 4 is a signaling diagram of a process for exchanging messages for channel change between an AP and a master AP, in accordance with the present invention. Figure 5 is a signaling diagram of a process for exchanging messages to reselect a master AP between an AP and a master AP, in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES In the following, the terminology "STA" includes but is not limited to a wireless transmitter / receiver unit (WTRU), a user equipment (UE), a fixed or mobile subscriber unit, a locator or any other another type of device capable of operating in a wireless environment. When referring to the following, the terminology "AP" includes but is not limited to a base station, a B-node, a site controller or any other type of interconnection device in a wireless environment. The features of the present invention can be incorporated into an integrated circuit (IC) or they can be configured in a circuit comprising a multitude of interconnecting components. Figure 1 shows an exemplary wireless communication system 100 with a WDS in which the present invention is implemented. The system 100 includes a plurality of AP 102a-102d. Each of the APs 102a-102d serves as its own BSS 106a-106d (or stand-alone BSS, collectively referred to herein as "BSS"), respectively. The APs 102a-102d are capable of sending WDS traffic via a WDS established between the APs 102a-102d. The WDS traffic can be a packet sent from an AP in a BSS to an AP in another BSS, or a packet sent from an STA in a BSS to an STA in another BSS. The APs 102a-102d fight over a WDS channel used for the WDS traffic so that the APs 102a-102d transmit and receive WDS traffic in the common WDS channel. APs 102a-102d may be equipped with a single radio transceiver (ie, APs need to share their radio transceiver for their own BSS traffic and WDS traffic) or more than one radio transceiver. The WDS channel that the APs 102a-102d fight may be different from the channel used to service the STAs I04a-104d by their own BSS 106a-106d (ie, the BSS channel), if the WDS channel is different from the BSS channel, the AP 102a-102d must be able to simultaneously receive packets on more than one channel. An AP 102a-102d may be able to fight for more than one WDS channel. In accordance with the present invention, at least one coordinated channel group (CCG) comprising a plurality of member APs is established. For example, in Figure 1, the APs 102a-102c belong to a CCG 108 and a common WDS channel is used for the WDS traffic in the CCG 108. In accordance with the present invention, the WDS channel can be dynamically changed and configured to coordinating the APs 102a-102c in the CCG 108. Being part of the CCG 108, the APs 102a-102c ensures that they maintain connectivity with all the other APs 102a-102c belonging to the CCG 108. In addition, the APs 102a-102c are they must ensure that they maintain connectivity with APs (such as AP 102d) that belong to other CCGs if certain rules are followed in the assignment of CCGs to APs. Certain APs may or may not have the ability to transmit packets to other APs in the WDS on a different sequence channel than the one in which they are located. In order to maintain connectivity with other WDS APs, an AP not equipped with this capability will never create a new CCG unless it is the only AP that is active in the environment. Similarly, the selection of the master of a CCG must be done manually by operation, administration and maintenance (OAM). If this approach is selected, the APs are not selected as master CCGs in the OAM configuration should be avoided in an attempt to create a new CCG (in which case they would automatically become masters of the newly created CCG). An AP can be part of many CCGs as the number of channels in which it is capable of camping. One of the AP 102a-102c of the CCG 108 is designated as the master AP (e.g. AP 102a). The master AP can be designated autonomously or manually by means of OAM. Master AP 102a accepts or rejects requests from other non-member APs (such as AP 102d) to be part of CCG 108, collects pertinent information from member APs 102b, 102c within the CCG 108 to make a change decision of WDS channel (which includes requests of the AP members 102b, 102c to make a channel change), executes a change of WDS channel and executes changes of other parameters (such as power transmission, a clear channel determination mode (CCA) (or similar), admission control parameters or other relevant operational settings) that may affect the operation of the system. CCA is a function that determines if the medium is occupied in IEEE 802.11. The CCA mode (or something similar in other types of systems) defines exactly how this determination is made (for example compare with a threshold or not, natural or signal or similar).

An AP 102a-102c that is part of the CCG 108 for a given WDS channel periodically broadcasts, multicast, or unicast a CCG indicator (CCGI) on the WDS channel. The CCGI is a unique identifier (for example a label, code, alphanumeric designation, number or similar). The CCGI can be included in an existing framework (such as a beacon frame or a probe response framework) or a self-sustaining (management) framework dedicated to the CCG functionality. The master AP 102a establishes a master indicator (e.g., flag or flag, or bit field or identification sequence) associated with the CCGI to indicate that the AP 102 is the master of the GCC 108. Only the master AP 102a establishes the master. master indicator. / Figure 2 is a signaling diagram of a process 200 for exchanging messages to join a CCG between a non-member AP and a master AP, according to the present invention. An AP that is not a member (such as the AP 102d) that wishes to join an existing CCG 108 sends an addition request message to CCG to the master AP 102a together with capacity information of the AP 102d or BSS information (step 202). The CCG addition request message includes the CCGI of the requested CCG 108. The capacity information includes, but is not limited to, the list of frequency channels in which the AP 102d is capable of camping information regarding the AP 102d is capable of reporting channel utilization or interference measurement. The BSS information is information related to the BSS served by the AP 102d (for example if the AP 102d uses the common channel or not to service its own BSS and, if so, how many STAs are currently served by the AP 102d). The master AP 102a determines whether the AP 102a that is not a member must be accepted or not and responds to the AP 102d that is not a member with a CCG addition response message, which indicates a positive or negative response (step 204). If the non-member AP 102d receives a positive response, the AP 102d becomes part of the CCG 108 and initiates the CCGI broadcast. The criteria for determining whether the non-member AP 102d should be accepted in the GCC 108 include, but are not limited to, insufficient capacities (for example, not being able to receive on certain channels) and the number of APs included in the CCG 108 (since if too many APs are included in the CCG 108, it may result in poor operation or unacceptable delays in changing the WDS channel of the CCG 108) or any other relevant factor. The master AP 102a can measure some factors on its own and these factors do not need to be communicated directly by the non-member AP 102d. For example, the master AP 102a can measure the channel load, interference, path loss between the non-member AP 102d and the master AP 102a or the signal strength received from the non-member AP 102d or the like. The CCG addition request message may be included in any conventional framework (e.g., a probe request message or association request message) or may be included in a new self-sustaining (management) framework. The CCG addition response message can also be included in any conventional framework (for example a probe response framework or an association response framework) or can be included in a new self-sustaining management framework). Figure 3 is a signaling diagram of process 300 for exchanging messages to leave a CCG between an AP and a master AP, according to the present invention. A member AP (such as the AP 102b) that wishes to leave the CCG 108 sends a CCG delay notification message to the master PA 102a (step 302). Upon receipt of the CCG delay notification message, the AP 102b no longer belongs to the GCC 108. The CCG deletion notification message can be included in any conventional framework (e.g., a dissociation message) or can be included in a new self-sustaining (management) framework. The member APs 102b, 102c of the CCG 108 preferably report measurements to the AP 102a master of the CCG 108. The measurements to be reported include not only measurements made by the APs 102b, 102c but also any measurements reported by the STAs 104b, 104c served by their own BSS 106b, 106c if the WDS channel is the same as the BSS channel used within its own BSS 106b, 106c. Relevant measurements that can be reported by each member AP 102b, 102c in support of channel management within the CCG 108 include, but are not limited to, interference levels measured on each channel, channel utilization of each channel, number of the STAs detected in each channel and addresses or identifiers of the STAs 104b, 104c currently associated with the APs 102b, 102c. If the BSS channel of the AP 102b, 102c is the same as the WDS channel, an AP member 102b, 102c may notify the master AP 102a of any relevant configuration modification (such as the association or dissociation of an STA 104b, 104c served by AP 102b, 102c). Figure 4 is a signaling diagram of a process 400 for exchanging messages for changing the WDS channel between a member AP 102b, 102c and a master AP 102a, according to the present invention. A member AP 102b, 102c experiences severe interference conditions in the currently selected WDS channel and may send a channel change request message to master AP 102a for change of WDS channel (step 402). The channel change request message may include a preference order for a new channel, as well as any relevant measurement information for selecting a new WDS channel. Upon receipt of the channel change request message, the master AP 102a may optionally respond to the requesting AP 102b, 102c with a channel change response message indicating that it accepts or rejects the request (step 404). The master AP 102a then determines whether a change of WDS channel is necessary (step 406). Alternatively, the channel change can be initiated by the master AP 102a without receiving the channel change request message. If the master AP 102a determines that the WDS channel change is necessary, the master AP sends all the member APs 102b, 102c of the CCG 108 a channel change instruction to change the WDS channel to a new channel (step 412). The channel change instruction includes synchronization information in which the channel change is executed. With respect to channel change synchronization, for those member APs that use the same channel for WDS traffic and BBS traffic on their BBS, master AP 102a may consider additional time so that these APs notify STAs of their BSS of the channel change. The master AP 102a can determine the additional time based on the number of STAs associated with these APs. Alternatively, master AP 102a may send (ie, broadcast, multicast, or unicast) a channel change preparation request message to all member APs 102b, 102c to inform member APs 102b, 102c of the WDS channel new to which the master AP 102a tries to change (step 408). Each member AP 102b, 102c in this way responds with a channel change preparation response message indicating the delay necessary for them in order to notify their STAs 104b, 104c of the channel change (step 410). Based on the responses of the member APs 102b, 102c, the master AP 102a determines the time at which the channel change will take place (probably using the largest delay reported by one of the member APs 102b, 102c) and signaling this time with the channel change instruction in step 410. An AP can create a new CCG. The AP that wants to create a new CCG selects a CCGI that is not used by any other CCG of the WDS. The AP first scans all frequency channels in which it is able to receive to detect all CCGIs in use in the WDS. To reduce the likelihood that the CCGI itself will be accidentally reused, the CCGI can randomly select within a predetermined interval. After the selection of the CCGI of the new CCG, the AP becomes the newly created CCG master and initiates the dissemination of the CCGI with the master indicator setting. When two or more CCGs are established, an AP can select a CCG to join the available CCGs. The selection of a CCG to which an AP is intended to join can be carried out autonomously by an AP or it can be configured manually by means of an operation and maintenance (OAM). Manual selection may be desirable in case there is a small number of APs in the WDS and it is expected that based on traffic requirements and AP capabilities, the best performance will be obtained when the APs are in the same WDS channel. When selecting the CCG, an AP considers the capabilities of different APs. Some APs may or may not have the ability to transmit packets to other WDS APs on a different channel than the one they are camping on. In order to maintain connectivity with other WDS APs, an AP that does not have this capability should never create a new CCG unless it is the only AP that is active in the environment. The master AP 102a can be selected and reselected manually or autonomously. If the master AP 102a is manually selected via OAM, the APs 102b, 102c are not selected since the master AP 102b is prevented from creating a new CCG (in which case it automatically becomes the master AP and the newly created CCG) . In manual configuration, a centrally located AP can be selected as the master AP to ensure good connectivity with other APs. Implicitly, the AP that created the CCG becomes the master AP. A master AP reselection procedure can be activated autonomously. For example, the master AP reselection procedure is activated when the master AP is inactivated, when the master AP wishes to release the CCG or when the master AP has transmitted nothing for a predetermined period, when the master AP mismatches its master indicator indicating that the master AP commits mastery or similar. In addition, any member AP 102, 102c can activate the master AP reselection procedure. Figure 5 is a signaling diagram of a method 500 for exchanging messages to reselect a new master AP between a member AP 102b, 102c and a current master AP 102a, in accordance with the present invention.

A member AP 102b, 102c sends a master AP reselection request message to the master AP 102a (step 502). Upon receipt of the message, the master AP 102a may optionally send a master AP reselection response message to the requesting AP 102b, 102c (step 504). The master AP 102a then mismatches its master indicator to indicate to all other member APs 102b, 102c that the master AP reselection procedure has been activated (step 506). Then a master AP reselection is performed by the member APs 102b, 102c and the master AP 102a (step 508). A new master AP can be selected by any appropriate means. For example, the new master AP can be selected by swapping the metrics associated with each of the APs in the CCG. For example, metrics can be traffic volume or just random numbers. The AP with the highest metric can be selected as the new master AP. A signaling between the APs and the master AP can be carried out as part of the protocol other than IEEE 802.11. For example, a generic network management protocol, such as simple network management protocol (SNMP) or extended markup language (XML) can be used to control, report and update operational parameters and settings that affect a selection of AP of the WDS and CCG channels. The adjustment parameters are stored in an AP database such as a management information base (MIB). Each AP may contain a software or program, hardware or physical elements or a combined routine that, on a regular activation basis, checks for updates of the parameters and settings contained in the AP database and adjust the behavior of the APs accordingly. . Alternatively, the program, the physical elements or the combined routine in the AP on a regular or activated basis look for updates of the settings parameters on a remote base relevant to a group of the APs or for all the APs. An L2 Ethertype or L3 control protocol can also be used to communicate signaling, bit fields and / or information elements. An AP may contain software, hardware or a combined communication routine that is inter-communicated between the L2 Ethertype control protocol or external L3 that is carried out in WDS or BSS based on IEEE 802.11. This adjusts the AP operational values directly after receiving said control protocol message L2 Ethertype or L3. Alternatively, you can indirectly adjust by means of one or more intermediate databases applicable to a single AP or an AP group.

MODALITIES 1. A method for autonomous channel coordination for the WDS in a wireless communication system that includes a plurality of APs, wherein the APs communicate with each other via a WDS. 2. The method of mode 1, which comprises the step of establishing a CCG comprising a plurality of member APs, the AP members of the CCG camp on a WDS channel used for the WDS between the member APs of the CCG. 3. The method of mode 2, which comprises the step of designating an AP between the AP members of the CCG as a master AP. 4. The method of mode 3, which comprises the step of having the master AP coordinate with other AP members of the CCG to select and configure the WDS channel for the CCG. 5. The method as in any of the modes 2-4, wherein each member AP of the CCG broadcasts a CCGI on the WDS channel. 6. The method of mode 5, where the CCGI is transmitted via a beacon frame and a probe response frame. 7. The method of mode 5, where the CCGI is transmitted via a self-sustaining framework. 8. The method as in any of the modes 3-7, where the master AP transmits a master indicator associated with the CCGI. 9. The method as in any of embodiments 3-8, further comprising the step that an AP that is not a member that wishes to join the CCG sends a CCG addition request message to the master AP. 10. The method of mode 9, which comprises the stage of which the master AP determines whether or not to accept the AP that is not a member. 11. The method of mode 10, comprising the step of the master AP sending a CCG addition response message to the non-member AP, the CCG addition response message indicating the acceptance or rejection of the request . 12. The method as in any of the embodiments 9-11, wherein the CCG admission request message includes capacity information of the non-member AP. 13. The method of mode 12, wherein the capacity information includes at least one of a list of frequency channels that a non-member AP can support, information as to whether the non-member AP is capable of report channel utilization and interference measurement and information related to a BSS served by the non-member AP. 14. The method as in any of the embodiments 9-13, wherein the CCG addition request message is included in one of a probe request message and association request message. 15. The method as in any of embodiments 11-14, wherein the CCG addition response message is included in one of a probe response message and an association response message. 16. The method as in any of the modalities 10-15, where the master AP considers at least one of the capabilities of the non-member AP and the number of the APs included in the CCG determines whether or not to accept the AP that is not a member. 17. The method as in any of the modalities 3-16, which also includes the stage of which the Member AP that wishes to leave the CCG sends a CCG deletion notification message to the master AP, whereby the master AP withdraws from the CCG. 18. The method of mode 17, wherein the notification message of deletion of CCG is included in a disassociation message. 19. The method as in any of the modes 3-18, which further comprises the stage of which each member AP reports measurements to the master AP, whereby the master AP selects and configures the WDS channel based on the reported measurements. 20. The method of mode 19, wherein the measurements include at least one level of interference measured on each channel, channel utilization of each channel, number of STAs detected on each channel and identities of STAs associated with each AP member. 21. The method as in any of the modes 19-20, where the measurements include measurements reported by STA associated with the member APs if the WDS channel is the same to a BSS channel used within its own BSS of the member APs. 22. The method as in any of the embodiments 3-21, further comprising the step of an AP member of the CCG sending a channel change request message to the master AP, whereby the master AP decides to change the WDS channel upon receipt of the channel change request message. 23. The method of mode 22, wherein the channel change request message includes a preference order for a new WDS channel. 24. The method as in any of the embodiments 22-23, further comprising the step of the master AP sending a channel change response message to the requesting member AP in response to a channel change request message.

. The method as in any of the modes 22-24, further comprising the step of the master AP sending a channel change instruction to the AP members of the CCG if the master AP decides to change the WDS channel. 26. The method as in any of the modes 2-25, which further comprises the stage of which an AP creates a new CCG, the AP becomes the master AP of the new CCG. 27. The method of mode 26, which includes the step of having the AP select a CCGI for a new CCG. 28. The method of modality 27, which includes the stage of the AP periodically disseminates the CCGI. 29. The method as in any of modes 27-28, wherein the AP randomly selects the CCGI within a predetermined range. 30. The method as in any of the modes 27-29, where the AP scans all frequency channels before selecting the CCGI. 31. The method as in any of the modes 3-30, wherein the member APs notify the master AP of any configuration modification if the BSS channel of the member APs is the same as the WDS channel. 32. The method as in any of modes 3-31, further comprising the step of which the master AP determines whether a change of WDS channel is necessary. 33. The method of mode 32, comprising the step of the master AP sending a channel change instruction if the master AP decides to change the WDS channel. 34. The method of mode 33, further comprising the step that the member AP sends a channel change request message to the master AP so that the master AP determines whether the change of WDS channel is necessary upon receipt of the request. channel change request message. 35. The method of mode 34, wherein the channel change request message includes an order or preference for a new channel. 36. The method as in any of the modes 33-35, wherein the channel change instruction includes synchronization information in which the channel change is executed. 37. The method of mode 36, where the master AP considers additional time for member APs that use the same channel for WDS traffic and BSS traffic in their BSS so that the member AP notifies STAs of their BSS of the channel change. 38. The method of mode 37, where the master AP determines the additional time based on the number of STAs associated with the member APs. 39. The method as in any of the embodiments 22-38, further comprising the step of the master AP sending a channel change preparation request message to the member APs to inform the AP members of the new WDS channel to the which tries to change the master AP. 40. The method of mode 39, comprising the step of each of the member APs responding with a channel change preparation response message indicating a necessary delay for their channel change STAs. 41. The method of mode 40, which comprises the step of having the master AP determine the additional time based on the delay indicated by the member APs. 42. The method as in any of embodiments 3-41, further comprising the step of activating a master AP reselection procedure, by means of which the new GCP master AP is selected. 43. The method of mode 42, wherein the reselection procedure of the master AP is activated at least one when the master AP is inactivated, when the master AP wishes to leave the CCG, when the master AP has transmitted nothing during a default period and when the master AP deactivates its master indicator indicating that the master AP renounces mastery. 44. The method of mode 42, wherein the reselection procedure of the master AP is activated by any AP member of the CCG that sends a master AP reselection request message to the master AP. 45. The method as in any of the modes 42-44, where the new master AP is selected by exchanging metrics associated with each of the APs in the CCG. 46. The method of mode 45, where the metrics are one of volume of traffic and random numbers. 47. The method as in any of the modes 3-46, wherein the signaling between the APs and the master AP is performed by one of SNMP, XML, L2 Ethertype protocol and L3 control protocol. 48. The method as in any of the modes 4-47, where the parameters of operational settings that affect an AP selection of the WDS and CCG channel are stored in an AP database, so that each AP checks for updates of the settings parameters contained in the AP database and adjusts the behavior of the APs accordingly. 49. The method as in any of the modes 4-47, where the parameters of operational settings that affect an AP selection of the WDS and CCG channel are stored in a remote database, so that each AP checks in search of updates the settings parameters contained in the remote database and adjusts the behavior of the APs accordingly. 50. A system for autonomous channel coordination for a WDS in a wireless communication system that includes a plurality of APs, wherein the APs communicate with each other via a WDS. 51. The mode 50 system, comprising a plurality of the member APs configured to establish a CCG, the member APs camp on a WDS channel used for the WDS between the member APs of the CCG. 52. The mode 51 system, comprising an AP that is designated from among the CCG member APs, the master AP is configured to coordinate with other CCG member APs to select and configure the WDS channel for the CCG. 53. The system as in any of the 51-52 modalities, where each member of the CCG disseminates a CCGI on the WDS channel. 54. The system of mode 53, where the CCGI is transmitted via a beacon frame and a probe response framework. 55. The system of mode 53, where the CCGI is transmitted via a self-sustaining framework. 56. The system as in any of the modes 53-55, where the master AP transmits a master indicator associated with the CCGI. 57. The system as in any of the embodiments 52-56, further comprising at least one non-member AP, configured to send a CCG addition request message to the master AP to join the CCG, wherein the AP teacher determines whether or not to accept the non-member AP and sends a CCG addition response message to the non-member AP indicating acceptance or rejection of the request. 58. The system of mode 57, where the CCG addition request message includes information capability of the AP that is not a member. 59. The system of mode 58, wherein the capacity information includes at least one of a list of frequency channels that a non-member AP can support, information as to whether the non-member AP is capable of report channel utilization and interference measurement and information related to a BSS served by the non-member AP. 60. The system as in any of embodiments 57-59, wherein the CCG addition request message is included in one of a probe request message and association request message. 61. The system as in any of embodiments 57-60, wherein the CCG addition response message is included in one of a probe response message and an association response message. 62. The system as in any of the modes 57-61, where the master AP considers at least one of the capacities of the non-member AP and the number of the APs included in the CCG determines whether or not to accept the AP that is not a member. 63. The system as in any of the modes 52-62, wherein a member AP that wishes to leave the CCG sends a CCG deletion notification message to the master AP, whereby the member AP withdraws from the CCG. 64. The system of mode 63, wherein the notification message of deletion of CCG is included in a disassociation message. 65. The system as in any of the modes 52-64, where each member AP is configured to report measurements to the master AP, whereby the master AP selects and configures the WDS channel based on the reported measurements. 66. The system of mode 65, where the measurements include at least one of the interference level measured in each channel, channel utilization of each channel, number of STAs detected in each channel and identities of the STAs associated with each AP member. 67. The system of mode 65, where the measurements include measurements reported by STA associated with the member APs if the WDS channel is the same to a BSS channel used within its own BSS of the member APs. 68. The system as in any of the modes 52-67, wherein the member AP is configured to send a channel change request message to the master AP, whereby the master AP decides to change the WDS channel upon receipt of the request. a channel change request message. 69. The system of mode 68, wherein the channel change request message includes an order of preference for a new WDS channel. 70. The system as in any of the modes 68-69, wherein the master AP is configured to send a channel change response message to the member AP that requested the channel change. 71. The system as in any of the modes 68-70, wherein the master AP is configured to send a channel change instruction to the AP members of the CCG if the master AP decides to change the WDS channel. 72. The system as in any of the modes 52-71, which also comprises at least one AP configured to create a new CCG, by selecting a CCGI for the new CCG, which becomes a new master CCG AP and periodically broadcast the CCGI. 73. The system of mode 72, wherein the AP randomly selects the CCGI within a predetermined interval. 74. The system of modality 72, where the AP scans all frequency channels before selecting the CCGI. 75. The system as in any of the modes 72-74, wherein the member APs are configured to notify the master AP of any configuration modification if a BSS channel of the member APs is equal to the WDS channel. 76. The system as in any of the modes 52-75, where the master AP is configured to determine if a change of WDS channel is necessary and send a change channel instruction if the master AP decides to change the WDS channel. 77. The system as in any of the modes 52-76, wherein the member AP is configured to send a channel change request message to the master AP, whereby the master AP determines whether the WDS channel change is necessary. upon receipt of the channel change request message. 78. The mode 77 system, wherein the channel change request message includes a preference order for a new channel. 79. The system as in any of the embodiments 76-78, wherein the channel change instruction includes synchronization information in which the channel change is executed. 80. The mode 79 system, where the master AP is configured to consider additional time for member APs that use the same channel for WDS traffic and BSS traffic in their BSSs so that the member AP notifies the STAs of your BSS's channel change. 81. The system of mode 80, wherein the master AP is configured to determine the additional time based on the number of STAs associated with the member APs. 82. The system as in any of the embodiments 76-81, wherein the master AP is configured to send a channel change preparation request message to the member APs to inform the member APs of the new WDS channel to which they are trying change the master AP 83. The system of mode 82, wherein each of the member APs is configured to respond via a channel change preparation response message indicating a delay necessary to notify its STA of the channel change, so that the Master AP determines the additional time based on the delay indicated by the member APs. 84. The system as in any of modes 52-83, wherein the member AP and the master AP are configured to activate a master AP reselection procedure, whereby a new master AP of the CCG is selected. 85. The system of mode 84, wherein the master AP reselection procedure is activated at least one when the master AP is inactivated, when the master AP wishes to leave the CCG, when the master AP has not transmitted anything during a default period and when the master AP decouples or uninstalls its master indicator indicating that the master AP relinquishes the master. 86. The mode 84 system, wherein the master AP reselection procedure is activated by any CCG member AP that sends a master AP reselection request message to the master AP. 87. The system as in any of the 84-86 modes, where the new master AP is selected by exchanging metrics associated with each of the APs in the CCG. 88. The system of mode 87, where the metrics are one of volume of traffic and random numbers. 89. The system as in any of the modes 52-88, wherein the signaling between the APs and the master AP is performed by one of SNMP, XML, L2 Ethertype protocol and L3 control protocol. 90. The system as in any of the modes 52-89, where the parameters and operational settings that fit an AP selection of the WDS and CCG channel are stored in an AP database, so each AP checks for updates of the settings parameters contained in the AP database and adjusts the behavior of the APs accordingly. 91. The system as in any of the modes 52-89, where the parameters of operational settings that affect an AP selection of the WDS and CCG channel are stored in a remote database, so that each AP checks in search of updates the settings parameters contained in the remote database and adjusts the behavior of the APs accordingly.

Although the features of elements of the present invention have been described in the preferred embodiments of particular combinations, each feature or element can be used alone without the other features or elements of the preferred embodiments or in various combinations with or without the other features and elements. of the present invention.

Claims (43)

1. Method for autonomous channel coordination, the method comprises: an access point (AP) that camps on a wireless distribution system (WDS) channel, the WDS channel is determined by a master AP of a coordinated channel group (CCG) comprising a plurality of AP members; and the AP sends a CCG indicator (CCGI) over the WDS channel.

2. Method as described in the claim 1, wherein the CCGI is transmitted via one of a beacon frame and a probe response frame.

3. Method as described in claim 1, wherein the CCGI is transmitted via a self-sustaining framework.

4. Method as described in claim 1, wherein the master AP transmits a master indicator associated with the CCGI. The method as described in claim 1, further comprising: the AP sends a CCG addition request message to the master AP; and the AP receiving a CCG addition response message from the master AP indicates acceptance or rejection. 6. Method as described in claim 5, wherein the CCG addition request message includes capacity information of the AP. The method as described in claim 6, wherein the capacity information includes at least one of a list of frequency channels that the AP can support, information as to whether the AP is capable of reporting channel utilization and measurement of interference and information related to a basic service set (BSS) served by the AP. The method as described in claim 5, wherein the CCG addition request message is included in one of a probe request message and an association request message. The method as described in claim 5, wherein the CCG addition response message is included in one of a probe response message and an association response message. The method as described in claim 5, wherein the master AP considers at least one of the AP capabilities and the number of member APs included in the CCG to determine whether or not to accept the AP. The method as described in claim 1, further comprising: the AP sending a CCG deletion notification message to the master AP when the AP is removed from the CCG. Method as described in claim 11, wherein the CCG deletion notification message is included in a disassociation message. 13. Method as described in claim 1, further comprising: the AP reports measurements to the master AP. The method as described in claim 13, wherein the measurements include at least one of the interference level measured on each channel, channel utilization of each channel, the number of stations (STA) detected on each channel and identities of each channel. STAs associated with the AP. The method as described in claim 13, wherein the measurements include measurements reported by the STAs associated with the AP if the WDS channel is the same to a basic service set (BSS) channel used within its own AP BSS . 16. Method as described in claim 1, further comprising: the AP sending a channel change request message to the master AP to change the WDS channel. The method as described in claim 16, wherein the channel change request message includes an order or preference for a new WDS channel. 18. Method as described in claim 16, further comprising: the AP receives a channel change instruction from the master AP; and the AP changes the WDS channel according to the channel change instruction. 19. Method as described in claim 1, wherein the master AP randomly selects the CCGI. 20. Method as described in claim 19, wherein the master AP scans all frequency channels before selecting the CCGI. The method as described in claim 1, wherein the AP notifies the master AP of any configuration modification if the basic service set (BSS) channel of the AP is the same for the WDS channel. 22. The method as described in claim 1, further comprising: the master AP determines whether a change of WDS channel is necessary; and the master AP sends a channel change instruction if the master AP decides to change the WDS channel. 23. The method as described in claim 22, further comprising: the AP sends a channel change request message to the master AP, whereby the master AP determines whether the change of the WDS channel is necessary upon reception of the channel change request message. 24. Method as described in claim 23, wherein the channel change request message includes a preference order for a new channel. 2

5. Method as described in claim 22, wherein the channel change instruction includes synchronization information about which channel change is executed. 2

6. Method as described in the claim 25, wherein the synchronization information is determined by considering a time necessary for the AP to notify the stations (STA) of the channel change if the AP uses the same channel for the WDS traffic and the basic service set traffic (BSS) ). 2

7. Method as described in the claim 26, where the master AP determines the additional time based on the number of STAs associated with the AP. 2

8. Method as described in the claim 26, further comprising: that the AP receiving a channel change prepares a request message from the master AP; and the AP responds with a channel change preparation response message indicating a delay necessary to notify STAs of the channel change. 2

9. The method as recited in claim 1, further comprising: the AP activates a master AP reselection procedure to select a new master AP of the CCG. 30. Method as described in claim 29, wherein the master AP reselection procedure is activated at least one when the master AP is inactivated, when the master AP wishes to leave the CCG, when the master AP has transmitted nothing. for a predetermined period and when the master AP deactivates its master indicator indicating that the master AP rejects mastery. 31. The method as described in claim 29, wherein the new master AP is selected by exchanging metrics associated with each of the APs in the CCG. 32. Method as described in claim 31, wherein the metrics are one of traffic volume and random numbers. 33. Method as described in the claim 1, wherein a signaling between AP and the master AP is performed by one of a simple network management protocol (SNMP), extended markup language (XML), L2 Ethertype protocol and L3 control protocol. 34. Access point (AP) for autonomous channel coordination, the AP comprises: a transceiver for transmitting and receiving a signal via a wireless distribution system (WDS) channel in a coordinated channel group (CCG) comprising a plurality of AP members; and a controller to configure the transceiver to camp on a WDS channel configured by a master AP of the CCG and send a CCG indicator (CCGI) periodically through the WDS channel. 35. Access point as described in claim 34, wherein the CCGI is transmitted via one of a beacon frame and a probe response frame. 36. Access point as described in claim 35, wherein the CCGI is transmitted via a self-sustaining framework. 37. Access point as described in claim 35, wherein the master AP transmits a master indicator associated with the CCGI. 38. Access point as described in claim 34, wherein the controller is configured to send a CCG addition request message to the master AP to join the CCG and receive a CCG addition response message indicating acceptance or rejection. 39. Access point as described in claim 38, wherein the CCG addition request message includes capacity information of the AP. 40. Access point as described in claim 39, wherein the capacity information includes at least one of a list of frequency channels that the AP can support, information as to whether the AP is capable of reporting channel utilization and measurement of interference and information related to a basic service set (BSS) served by the AP. 41. Access point as described in claim 38, wherein the CCG addition request message is included in one of a probe request message and an association request message. 42. Access point as described in claim 38, wherein the CCG addition response message is included in one of a probe response message and an association response message. 43. Access point as described in claim 34, where the controller sends a CCG deletion notification message to the master AP to be removed from the CCG. Four . Access point as described in claim 43, wherein the CCG deletion notification message is included in a disassociation message. 45. Access point as described in claim 34, wherein the controller is configured to report measurements to the master AP. 46. Access point as described in claim 45, wherein the measurements include at least one of the interference level measured on each channel, channel utilization of each channel, number of stations (STA) detected on each channel and identities of the STAs associated with the AP. 47. Access point as described in claim 45, wherein the measurements include measurements reported by the STAs associated with the AP if the WDS channel is the same as a basic service set channel (BSS). 48. Access point as described in claim 34, wherein the controller sends a channel change request message to the master AP to select a new WDS channel. 49. Access point as described in claim 48, wherein the channel change request message includes a preference order for a new WDS channel. 50. Access point as described in claim 48, wherein the controller receives a channel change instruction from the master AP and changes the WDS channel according to the channel change instruction. 51. Access point as described in claim 34, wherein the controller is configured to notify the master AP of any configuration modification if the basic service set channel (BSS) is the same as the WDS channel. 52. Access point as described in claim 50, wherein the channel change instruction includes synchronization information about which channel change is executed. 53. Access point as described in claim 34, wherein the controller is configured to activate a master AP reselection procedure to select a new master AP. 54. Access point as described in claim 53, wherein the controller activates the master AP reselection procedure in at least one when the master AP is inactive, when the master AP wishes to leave the CCG, when the master AP it has not transmitted anything for a predetermined period and when the master AP deactivates its master indicator indicating that the master AP renounces mastery. 55. Access point as described in claim 53, wherein the new master AP is selected by exchanging metrics associated with each of the APs in the CCG. 56. Access point as described in claim 55, wherein the metrics are one of traffic volume and random numbers. 57. Access point as described in claim 34, wherein a signaling between the AP and the master AP is performed by a simple network management protocol (SNMP), extended markup language (XML), L2 Ethertype protocol and L3 control protocol. 58. Access point as described in claim 57, further comprising: a database for storing operations and settings parameters that affect the selection of the AP of the WDS and CCG channel. 59. Access point as described in claim 57, wherein the controller is configured to retrieve operational parameters and settings that affect the AP selection of the WDS and CCG channel from a remote database.