Collaboratively locating disconnected clients and rogue access points in a wireless network

• US 8,086,227 B2
• Filed: 11/15/2007
• Issued: 12/27/2011
• Est. Priority Date: 09/24/2004
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Adya, Atul, Bahl, Paramvir, Chandra, Ranveer, Qiu, Lili
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Gonzalez, Amancio
• Application Number:
  US11/940,466
• Publication Number:
  US 20080070563A1
• Time in Patent Office: 1,503 Days
• Field of Search: 455/456.2, 455/67.11, 455/456.1, 455/421, 455/436, 702/150
• US Class Current: 455/421
• CPC Class Codes: H04W 12/122 Counter-measures against attacks; Protection against rogue devices
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Methods are described for using collaboration of neighboring wireless devices to enable location of disconnected wireless devices and rogue wireless access points. A central server computes the locations of the neighboring clients and uses those locations to estimate the location of a disconnected client. These techniques may take advantage of the beaconing and probing mechanisms of IEEE 802.11 to ensure that connected clients do not pay unnecessary overheads for detecting disconnected clients. Methods are also described for detecting and locating rogue devices by collaboratively collecting information from neighboring devices and comparing the information to a database.

Claims

1. A method for a first wireless client to indicate that it is unable to connect to an infrastructure network, the method comprising acts performed by the first wireless client of:

attempting to connect to the infrastructure network;

determining that it is unable to connect to the infrastructure network; and

broadcasting, in response to determining that it is unable to connect to the infrastructure network, a signal indicating that it is unable to connect to the infrastructure network,

wherein multiple other wireless clients in the vicinity of the first wireless client each perform the acts of;

receiving the signal from the first wireless client;

recording the signal strength of the received signal from the first wireless client; and

transmitting the recorded signal strength of the received signal from the first wireless client to a diagnostic server for estimating, by the diagnostic server, the location of the first wireless client.

2. The method of claim 1, wherein the act of determining that the first client is unable to connect to the infrastructure network further comprises an act of determining that it is unable to connect to the infrastructure network by failing to receive any beacon signals transmitted from an access point.

3. The method of claim 1, wherein the act of determining that the first client is unable to connect to the infrastructure network further comprises an act of determining that it is unable to connect to the infrastructure network by failing to receive any probe response signals transmitted from an access point in response to a probe request signal transmitted by the first client.

4. The method of claim 1, wherein the act of broadcasting a signal indicating that the first client is unable to connect to the infrastructure network further comprises an act of broadcasting a beacon signal indicating that the first client is unable to connect to the infrastructure network.

5. The method of claim 1, wherein the infrastructure network operates according to the IEEE 802.11 protocol.