Fine-grained location determination of networked computers

• US 8,307,071 B2
• Filed: 01/15/2010
• Issued: 11/06/2012
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Donnelly, Austin, Aboba, Bernard, Kuntz, Roy, Montenegro, Gabriel, Singh, Noor-E-Gagan, Moore, Tim
• Primary Examiner(s): Donaghue, Larry
• Assistant Examiner(s): TAYLOR, NICHOLAS R
• Application Number:
  US12/688,047
• Publication Number:
  US 20110179158A1
• Time in Patent Office: 1,026 Days
• Field of Search: 709/224, 709/203, 709/221
• US Class Current: 709/224
• CPC Class Codes: H04L 67/306 User profiles
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04L 67/535 Tracking the activity of the user network monitoring arrangements H04L43/00; recording of computer activity G06F11/34
• CPC Class Codes: H04M 15/8033 location-dependent, e.g. business or home
• CPC Class Codes: H04M 3/42348 Location-based services which utilize the location information of a target
• CPC Class Codes: H04M 3/5116 for emergency applications
• CPC Class Codes: H04Q 2213/13097 Numbering, addressing
• CPC Class Codes: H04Q 2213/13098 Mobile subscriber
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13141 Hunting for free outlet, circuit or channel
• CPC Class Codes: H04Q 2213/1337 Operator, emergency services

Abstract

Location of a communication network subscriber is determined employing confidence metrics such as remote vs. local computer usage, primary user in a multi-user computing environment, likelihood of forgery, and comparable ones. A fine-grained location determination is then made based on the metric results and directory information for the particular subscriber such that services like emergency services can be provided with accurate location information.

Claims

1. A method to be executed at least in part in a computing device for location determination in networked communication systems, the method comprising:

determining whether a target computing device is mainly used locally;

if the target computing device is mainly used locally, determining whether the target computing device is a multi-user device;

if the target computing device is a multi-user device, determining whether a user of interest is a primary user of the target computing device;

if the user of interest is the primary user of the target computing device, retrieving physical location information for the user of interest;

determining a confidence metric based on one or more of a local use to remote use ratio, on a peak usage ratio for local users of the target computing device, and input from the user of interest;

assigning a low confidence value to the confidence metric if the confidence metric is determined based on the input from the user of interest; and

providing the physical location information and the confidence metric to a location-based service.

2. The method of claim 1, wherein the location-based service is an emergency response service and the user of interest is a person reporting an emergency through a communication application executed on the target computing device.

3. The method of claim 1, further comprising:

assigning a high confidence value to the confidence metric if the target computing device is determined to be a single user computing device.

4. The method of claim 1, further comprising:

determining whether the target computing device is mainly used locally based on events including at least one from a set of;

login, logout, reconnect, disconnect, boot, reboot, shutdown, workstation lock, workstation unlock, and screensaver dismissal.

5. The method of claim 1, further comprising:

determining the physical location information at one of;

a periodic and a random interval; and

performing a verification of the physical location information in response to a request from the location-based service.

6. The method of claim 1, further comprising:

determining the confidence metric based on comparing a local-to-remote use ratio to a first threshold and comparing a peak use ratio to a second threshold, wherein the first and second thresholds are determined based on at least one from a set of;

a target computing device type, a network type, a time of day, a number of computing devices in the network, a usage pattern, and a geo-distribution of the computing devices.

7. A computing device for providing fine-grained location information in a networked communication system, the computing device comprising:

a communication component for communication with a plurality of client devices;

a memory;

a processor coupled to the memory, the processor executing a location information service for performing actions including;

determine a local use ratio (L/R) for a target client device;

if the L/R is above a first threshold, determine a peak use ratio (P/M) for the target client device;

if the P/M is below a second threshold determine a primary user for the target client device from one of;

a user input and an administrator input;

compute a confidence metric based on the L/R and the P/M;

retrieve physical location information for the primary user of the target client device from a directory service;

provide the physical location information and the computed confidence metric to a location-based service;

request a location testament from a trusted location certification server in response to receiving a request from the location-based service; and

receive the location testament generated based on comparing the target client device'"'"'s location and identifier to the location and identifier of at least one other client device in the same witness set.

8. The computing device of claim 7, wherein the location information service is further configured to perform actions including:

select a predefined number of client devices on a same subnet as the target client device to act as a witness set; and

verify a location of the target client device by comparing the target client device'"'"'s location within the network compared to a witness set at about the same location within the network.

9. The computing device of claim 8, wherein the verification is performed by examining at least one randomly selected client device of a witness set and confirming that the client devices are on the same subnet.

10. The computing device of claim 7, wherein the L/R and the P/M are determined based on examining events associated with the target client device, the events being recorded over a predefined period such that exceptional occasions are appropriately captured.

11. The computing device of claim 7, wherein the first and second thresholds are determined and dynamically adjusted based on at least one from a set of:

a target client device type, a network type, a time of day, a number of client devices in the network, a usage pattern, and a geo-distribution of the client devices.

12. A computer-readable memory device with instructions stored thereon for location determination in networked communication systems, the instructions comprising:

selecting a predefined number of computing devices on a same subnet as a target computing device to form a witness set;

determining a local vs. remote use ratio for a target computing device;

determining a primary usage ratio for the target computing device;

maintaining a mapping from the target computing device to least one from a set of;

a physical location, a network identifier, a machine identifier, a timestamp, and a confidence metric, wherein the confidence metric is determined based on one or more of the local vs. remote use ratio, on the primary usage ratio for the target computing device, and input from a user of interest;

assigning a low confidence value to the confidence metric if the confidence metric is determined based on the input from the user of interest;

verifying a location for the target computing device based on mapped information in response to a request from a location-based service; and

providing the verified location and the mapped information for the target computing device in response to the request to the location-based service.

13. The computer-readable memory device of claim 12, wherein the instructions further comprise:

presenting at least a portion of the mapped information to an administrator;

receiving administrator confirmation; and

storing the confirmed portion of the mapped information as high-confidence entries.

14. The computer-readable memory device of claim 13, wherein the instructions further comprise:

if the target computing device is a single user device, storing the mapped information for the target computing device as a high-confidence entry;

if the target computing device is a multi-user device and the primary usage ratio is below a predefined threshold, requesting user input from the target computing device and storing the mapped information for the target computing device as a low-confidence entry; and

if the target computing device is a multi-user device and user input has been received from the target computing device, verifying the received user input by examining computing devices in the associated witness set and storing the mapped information for the target computing device as a witness set verified high-confidence entry.

15. The computer-readable memory device of claim 12, wherein a frequency of determination for the local vs. remote use ratio and primary usage ratio, and a frequency of the verification are determined based on historic change records associated with the target computing device.