System and method for passive scanning of authorized wireless channels

• US 7,466,678 B2
• Filed: 12/29/2003
• Issued: 12/16/2008
• Est. Priority Date: 12/29/2003
• Status: Active Grant

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Inventors: Cromer, Daryl Carvis, Locker, Howard Jeffrey, Jakes, Philip John, Griffiths, Ronald John Jr.
• Primary Examiner(s): Chan; Wing F
• Assistant Examiner(s): Tsegaye; Saba
• Application Number:
  US10/747,575
• Publication Number:
  US 20050147070A1
• Time in Patent Office: 1,814 Days
• Field of Search: 370/328, 370/329, 370/331, 370/338, 370/341, 370/343, 455/422.1, 455/450
• US Class Current: 370/331
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A wireless device operating under the IEEE 802.11 specifications passively scans for a wireless access point coupled to a network backbone, wherein the scanning is performed using a default set of channels. The wireless device will then determine if the access point operates under an IEEE 802.11d specification, thus providing a country code to the wireless device. The wireless device will then utilize the country code to determine if the wireless device is legally authorized to communicate with the selected access point with wireless signal channels in addition to the default set of channels. The wireless device can then communicate with a selected access point utilizing any of the default set of channels and the wireless signal channels in addition to the default set of channels.

Claims

1. In a wireless device, a method comprising the steps of:

passively scanning for a wireless signal transmitted from an access point, wherein the scanning is performed using a default set of frequencies;

determining if a selected access point is providing a geographical indicator to the wireless device, wherein the geographical indicator informs the wireless device where the access point is geographically located;

utilizing the geographical indicator to determine if the wireless device is authorized to communicate with wireless signal frequencies in addition to the default set of frequencies;

re-scanning for a wireless signal transmitted from an access point, wherein the re-scanning is performed using the wireless signal frequencies in addition to the default set of frequencies;

in response to the re-scanning step, selecting an access point to communicate through to the network backbone; and

the wireless device communicating with the selected access point utilizing any of the default set of frequencies and the wireless signal frequencies in addition to the default set of frequencies;

wherein the wireless device determines if it is authorized to communicate with the selected access point with wireless signal frequencies in addition to the default set of frequencies by determining if has loaded a certificate indicating such authority.

2. The method as recited in claim 1, further comprising the step of:

loading the default set of frequencies upon power up of the wireless device.

3. The method as recited in claim 1, wherein the geographical indicator is a country code sent in a wireless signal from the selected access point to the wireless device indicating in what country of the world the selected access point is located.

4. The method as recited in claim 3, wherein the selected access point operates under an IEEE 802.11d specification.

5. The method as recited in claim 1, further comprising the steps of:

the wireless device periodically accessing a certificate server over a network backbone; and

downloading any new certificates from the certificate server in order to provide the wireless device with authorization to communicate with access points utilizing frequencies in addition to the default set of frequencies.

6. A wireless device operating under IEEE 802.11 specifications, comprising:

circuitry for passively scanning for a wireless access point coupled to a network backbone, wherein the scanning is performed using a default set of channels;

circuitry for determining if the access point operates under an IEEE 802.11d specification, providing a geographical indicator to the wireless device, wherein the geographical indicator informs the wireless device where the access point is geographically located;

circuitry for utilizing the geographical indicator to determine if the wireless device is legally authorized to communicate with wireless signal channels in addition to the default set of channels; and

circuitry for communicating with a selected access point utilizing any of the default set of channels and the wireless signal channels in addition to the default set of channels;

wherein the geographical indicator is a country code sent in a wireless signal from the selected access point to the wireless device indicating in what country of the world the selected access point is located;

wherein the wireless device determines if it is legally authorized to communicate with the selected access point with wireless signal channels in addition to the default set of channels by determining if has loaded a certificate indicating such authority.

7. The device as recited in claim 6, further comprising:

circuitry for loading the default set of channels upon power up of the wireless device.

8. The device as recited in claim 6, wherein the set of default channels is channels 1-11 under the IEEE 802.11 specifications, and wherein the wireless signal channels in addition to the default set of channels may include any one or more of channels 12-14.