Directed station roaming in cloud managed Wi-Fi network

Patent metadata

Field	Value
Publication number	US-9635597-B2
Application number	US-201615366096-A
Country	US
Kind code	B2
Filing date	Dec 1, 2016
Priority date	Jul 29, 2015
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

Directing station roaming in a cloud-managed Wi-Fi network. Management messages are received from a controller that is located remotely from the Wi-Fi communication network by an access point. When an RSSI (received signal strength indication) value between the station and the access point falls below a threshold, the access point (i.e., controller access point) determines which neighboring access point would be a best fit for a hand-off, with limited real-time input form the cloud-based Wi-Fi controller. One of the two or more of the plurality of access points is selected for handing-off the station based on the RSSI values received from the interrogation. Responsive to the selection, a message is sent to the selected access point instructing the one of the at least one of the plurality of access points to respond to messages from the station.

First claim

I claim:

1. A computer-implemented method in an access point on a local area network for directing station roaming in a cloud-managed Wi-Fi communication network, the method comprising the steps of:
receiving management messages from a controller that is located remotely from the Wi-Fi communication network wherein the access point is one of a plurality of access points each managed by a controller located external to the local area network;
associating a station with the access point that serves as a controller access point for the station, wherein others of the plurality of access points serve as controller access points for other stations;
detecting that an RSSI (received signal strength indication) value between the station and the access point falls below a threshold;
responsive to falling below the threshold, interrogating at least one of the plurality of access points for a change in RSSI values between the station and the two or more of the plurality of access points, the change in RSSI values indicative of a direction of movement of the station;
selecting one of the two or more of the plurality of access points for handing-off the station based on the combination of the change in RSSI values received from the interrogation and the management messages; and
responsive to the selection, sending a message to the selected access point, the message instructing the one of the at least one of the plurality of access points to respond to messages from the station.

2. The method of claim 1 wherein, a different access point from the plurality of access points is appointed the controller access points, performs the above steps of the access point.

3. The method of claim 1 , further comprising:
reducing power to the station to compel the station to initiate a hand-off.

4. The method of claim 1 , further comprising:
receiving the change in RSSI values responsive to the interrogation.

5. The method of claim 1 , further comprising:
receiving the change in RSSI values along with other local conditions responsive to the interrogation; and
selecting one of the two or more of the plurality of access points is based on a weighted combination of the change in RSSI values and other local conditions received from the interrogation.

6. The method of claim 1 , wherein access points within the plurality of access points not selected to for hand-off of the stations ignore messages from the station.

7. The method of claim 1 , wherein the access point and the selected access point use the same BSSID (basic service set identifier) for messages with the station, and wherein the hand-off from the access point to the selected access point is substantially transparent to the station.

8. The method of claim 1 , further comprising:
switching to a safety mode in which selection of access points for station roaming is returned to the cloud-based Wi-Fi controller.

9. A non-transitory computer-readable medium storing source code that, when executed by a processor, performs a method in an access point on a local area network for directing station roaming in a cloud-managed Wi-Fi communication network, the method comprising the steps of:
receiving management messages from a controller that is located remotely from the Wi-Fi communication network wherein the access point is one of a plurality of access points each managed by a controller located external to the local area network;
associating a station with the access point that serves as a controller access point for the station, wherein others of the plurality of access points serve as controller access points for other stations;
detecting that an RSSI (received signal strength indication) value between the station and the access point falls below a threshold;
responsive to falling below the threshold, interrogating at least one of the plurality of access points for a change in RSSI values between the station and the two or more of the plurality of access points, the change in RSSI values indicative of a direction of movement of the station;
selecting one of the two or more of the plurality of access points for handing-off the station based on the combination of the change in RSSI values received from the interrogation and the management messages; and
responsive to the selection, sending a message to the selected access point, the message instructing the one of the at least one of the plurality of access points to respond to messages from the station.

10. The non-transitory computer-readable medium of claim 9 wherein, a different access point from the plurality of access points is appointed the controller access points, performs the above steps of the access point.

11. An access point on a local area network for directing station roaming in a cloud-managed Wi-Fi communication network, the access point comprising:
a processor; and
a memory, storing:
a first module to receive management messages from a controller that is located remotely from the Wi-Fi communication network wherein the access point is one of a plurality of access points each managed by a controller located external to the local area network;
a second module to associate a station with the access point that serves as a controller access point for the station, wherein others of the plurality of access points serve as controller access points for other stations;
a third module to detect that an RSSI (received signal strength indication) value between the station and the access point falls below a threshold;
a fourth module to, responsive to falling below the threshold, interrogating at least one of the plurality of access points for a change in RSSI values between the station and the two or more of the plurality of access points, the change in RSSI values indicative of a direction of movement of the station;
a fifth module to select one of the two or more of the plurality of access points for handing-off the station based on the combination of the change in RSSI values received from the interrogation and the management messages; and
a sixth module to, responsive to the selection, send a message to the selected access point, the message instructing the one of the at least one of the plurality of access points to respond to messages from the station.

12. The access point of claim 11 wherein, a different access point from the plurality of access points is appointed the controller access points, performs the above steps of the access point.

Assignees

• Fortinet Inc

Inventors

• Kaushik Anil

Classifications

• H04B17/318 Primary

  Received signal strength · CPC title

• H04W52/40

  during macro-diversity or soft handoff · CPC title

• H04W36/38 Primary

  by fixed network equipment · CPC title

• H04W36/08

  Reselecting an access point · CPC title

• H04L67/10

  in which an application is distributed across nodes in the network (software deployment G06F8/60; multiprogramming arrangements G06F9/46) · CPC title