Method and apparatus for dormant mode support with paging

A method for establishing a plurality of paging areas in a WLAN, wherein the WLAN enables dormant mode with paging and comprises a plurality of access points, comprising:

• forming a plurality of access point groups, wherein each of the plurality of access point groups is formed from a subset of the plurality of access points, has a tree structured distributed grouping model as the structure, and defines a paging area, comprising:
• assigning at least one role to each of the access points in the access point group, wherein the roles comprise master and slave;
• and
• associating each access point assigned the master role with at least one access point assigned the slave role and associating each access point assigned the slave role with exactly one access point assigned the master role;
• the protocol established for communications among the plurality of access points is an IEEE Inter Access Point Protocol;
• establishing a protocol for manipulating access point groups comprises modifying the IEEE Inter Access Point Protocol by adding a join operation, a leave operation, a group merge operation, a group prune operation and a group devolution operation;
• assigning each of the plurality of access point groups a unique paging area identification number;
• and
• having each of the access points in each of the plurality of access point groups broadcast the paging area identification number associated with each access point's access point group throughout each access point's access point group.

A method for synchronizing a beacon timing of a first access point with a beacon timing of a second access point wherein the first and second access points are in an access point group in a WLAN, comprising:

• calculating the difference between the beacon timing of the first access point and the beacon timing of the second access point to ascertain a beacon timing difference, wherein the calculating is performed by a computing device;
• communicating the beacon timing difference from the computing device to the second access point and the first access point;
• and
• adjusting the beacon timing of either the first access point or the second access point so that the beacon timing of the either the first access point or the second access point equals the beacon timing of the other of the first access point or the second access point.

A method for synchronizing a beacon timing of a first access point with a beacon timing of a second access point wherein the first and second access points are in an access point group in a WLAN, comprising:

• calculating the difference between the beacon timing of the first access point and the beacon timing difference of the second access point to ascertain a beacon timing difference, wherein the calculating is performed by a computing device, comprising:
• while the computing device is within a range of the first access point, periodically shifting the computing device into an active mode to detect a first access point beacon broadcast at least one predetermined time for a predetermined time interval, wherein the at least one predetermined time corresponds to a beacon timing of the first access point;
• moving the computing device from within the range of the first access point to within a range of the second access point;
• while the computing device is within the range of the second access point, periodically shifting the computing device into the active mode to detect a second access point beacon broadcast at one of the at least one predetermined times for a time interval, wherein the time interval ends when the computing device detects the beacon broadcast of the second access point;
• and
• subtracting the one of the at least one predetermined times from the time interval to calculate the beacon timing difference;
• communicating the beacon timing difference from the computing device to the second access point and the first access points, comprising:
• the computing device communicating the beacon timing difference to the second access point;
• the second access point identifying the first access point;
• the second access point communicating the beacon timing difference to the first access point;
• and
• adjusting the beacon timing of either the first access point or the second access point so that the beacon timing of either the first access point or the second access point equals the beacon timing of the other of the first access point or the second access point, comprising:
• if either the first access point or the second access point is a master of the other of the first or the second access point, wherein the other of the first access point or the second access point is a slave of the master access point, adjusting the beacon timing of the slave access point to the beacon timing of the master access point;
• and
• if neither the first access point or the second access point is a master of the other of the first access point or the second access point, determining a common master access point and adjusting the beacon timing of the first access point and the beacon timing of the second access points to a beacon timing of the common master access point.

A method for associating a computing device with a new access point group in a WLAN whenever the computing device crosses an access point boundary, wherein the new access point group comprises a plurality of access points, comprising:

• discovering when the computing device has crossed an access point boundary;
• the computing device sending a request to the new access point group;
• and
• assigning an association identification number to the computing device.

A method for associating a computing device with a new access point group in a WLAN whenever the computing device crosses an access point boundary, wherein the new access point group comprises a plurality of access points, comprising:

• discovering when the computing device has crossed an access point boundary, comprising the computing device detecting a group identification in the beacon broadcast of one of the plurality of access points in the new access point group and determining the beacon broadcasts of the one of the plurality of access points in the new access point group is stronger than a beacon broadcast of one of a plurality of access points in an old access point group;
• the computing device sending a request to the new access point group, comprising:
• the computing device sending the request to one of the plurality of access points in the access point group;
• and
• if the one of the plurality of access points in the access point group is not a root access point, communicating the request to a root access point;
• and
• assigning an association identification to the computing device, wherein assigning an association identification to the computing device is performed by the root access point.

A method of communicating access point group information to a computing device, comprising:

• including a paging area identification of each of at least two access point groups in a beacon of each of the respective access point groups;
• assigning a channel to each of the beacons;
• each of the at least one access point groups broadcasting the beacon for that access point group within the paging area defined by that access point group;
• periodically awakening the at least one computing device to detect the beacon of at least one of the at least one access point groups;
• and
• synchronizing a timing of the beacons.

A WLAN with paging, comprising:

• a plurality of access points;
• at least two access point groups, wherein each of the at least two access point groups comprises a subset of the plurality of access points related according to a distributed grouping model;
• at least two paging areas wherein each of the at least two paging areas comprises a paging area boundary and is defined by one of the at least two access point groups;
• a protocol for communications among the plurality of access points;
• and
• a protocol for manipulating the access point groups.

A WLAN, comprising:

• a means for establishing paging areas;
• a means for communicating access group information to a computing device;
• and
• a means for locating a computing device within the WLAN.

A method for implementing dormant mode with paging in a WLAN, comprising:

• establishing paging areas;
• communicating access group information to a computing device;
• and
• locating a computing device. PAGE 56