Method for disseminating geolocation information for network infrastructure devices

• US 8,340,682 B2
• Filed: 07/06/2006
• Issued: 12/25/2012
• Est. Priority Date: 07/06/2006
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Taylor, Kirk S., Steenstra, Jack, Chen, Liren
• Primary Examiner(s): Figueroa, Marisol
• Application Number:
  US11/483,067
• Publication Number:
  US 20080101277A1
• Time in Patent Office: 2,364 Days
• Field of Search: 455/456.1
• US Class Current: 455/456.1
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

A scheme is provided for distributing reference geographical locations on a network. Geolocation information is integrated or associated with one or more network infrastructure devices to permit them to serve as reference points for the rest of the network. A reference geographical location associated with a network infrastructure device may be broadcast by the network infrastructure device over a network. Alternatively, other network devices may request reference geographical location from a network infrastructure device or obtain it from a network-accessible database that stores such geolocation information. Other network devices can then use the one or more reference geographical locations to determine their own geographical location. By allowing existing network devices to take advantage of the geolocation capability of its “neighboring” network devices, this scheme provides a convenient way to deliver geolocation to many network devices.

Claims

1. A method for disseminating geographical location information between network devices, comprising:

obtaining a geographical location of a reference network device;

storing the geographical location; and

supporting a network time protocol that facilitates distance estimation between the reference network device and one or more other network devices by synchronizing their clocks;

wherein the geographical location is provided to at least one of the one or more other network devices for determining a geographical location of the at least one of the one or more other network devices using packet exchanges based on the clock synchronization; and

wherein a mechanism is provided to selectively identify and authenticate at least one network device as being authorized to act as the reference network device to the at least one of the one or more other network devices.

2. The method of claim 1, further comprising:

monitoring for a change in the geographical location of the reference network device and updating the geographical location when the monitoring indicates a change in the geographical location of the reference network device.

3. The method of claim 1, wherein the geographical location includes a longitude and a latitude.

4. The method of claim 1, wherein the geographical location is automatically propagated to the one or more other network devices.

5. The method of claim 1, wherein the geographical location of the reference network device is obtained from an onboard global positioning device.

6. The method of claim 1, wherein the geographical location of the reference network device is manually configured into the reference network device.

7. The method of claim 1, wherein the geographical location of the reference network device is obtained by:

acquiring one or more reference geographical locations for other reference network devices;

determining one or more distances from the reference network device to each of the one or more reference geographical locations; and

deriving the geographical location of the reference network device based on the one or more reference geographical locations of the other reference network devices and the one or more distances.

8. The method of claim 7, wherein the one or more reference geographical locations are obtained from a root reference server on the network.

9. The method of claim 1, further comprising:

including an indication of a level of accuracy of the geographical location in the geographical location of the reference network device, wherein the level of accuracy indicates a number of hops on the communication network that the reference network device is located from a source device with a geographic location information having a highest level of accuracy; and

providing the level of accuracy indication along with the geographical location.

10. The method of claim 9, wherein the level of accuracy indication is determined based on one or more level of accuracy indications associated with one or more reference geographical locations for other reference network devices.

11. The method of claim 9, further comprising:

updating the geographical location of the reference network device using only one or more other reference network device with a geographical location having a level of accuracy indication indicating an equal or greater accuracy than the level of accuracy of the reference network device.

12. The method of claim 1, further comprising:

appending an expiration timestamp to the geographical location provided to the at least one of the one or more other network devices, wherein the expiration timestamp indicates how long the geographical location can be relied on.

13. The method of claim 1, wherein the mechanism further authorizes the reference network device to provide its geographical location to the at least one of the one or more other network devices.

14. The method of claim 1, wherein the geographical location of the reference network device is obtained by:

obtaining a reference geographical location associated with a second reference network device;

synchronizing a first clock in the reference network device with a second clock in the second reference network device, the synchronized first and second clocks facilitating a direct one-way trip time measurement between the reference network device and the second reference network device;

obtaining a one-way distance between the reference network device and the second reference network device based on the direct one-way trip time measurement; and

obtaining the geographical location associated with the reference network device based on the reference geographical location and the one-way distance.

15. The method of claim 14, wherein the direct one-way trip time measurement is performed for both a transmit path from the reference network device and a receive path to the reference network device, and a one-way distance between the reference infrastructure network device and the second reference network device based on the direct one-way trip time measurement is determined for each of the transmit path and the receive path, the shorter of the one way distance of the transmit path and the receive path is employed to obtain the geographical location.

16. The method of claim 15, wherein the transmit path has a different transmission speed than the receive path.

17. The method of claim 14, further comprising:

determining the transmission medium between the reference network device and the second reference network device;

determining a propagation speed of the transmission medium;

obtaining a propagation time between the reference network device and the second reference network device based on the transmission medium propagation speed between the reference network device and the second reference network device; and

obtaining the geographical location associated with the reference network device based on the reference geographical location and the propagation time.

18. The method of claim 1, wherein the one or more other network devices are restricted to network devices positioned within a threshold number of network hops to the reference network device.

19. The method of claim 1, wherein a mechanism is provided to selectively identify and authenticate the at least one of the one or more other network devices as being authorized to request the geographical location.

20. The method of claim 1, wherein the mechanism selectively identifies and authenticates at least one network device as being authorized to act as the reference network device to all of the one or more other network devices.

21. The method of claim 1, wherein the mechanism comprises one or more of an authorization key or a unique key, or combinations thereof.

22. The method of claim 1, wherein the reference network device operates within a transmission line based communication network, and wherein the geographical location is provided to the at least one of the one or more other network devices on the transmission line based communication network.

23. The method of claim 1, wherein the geographical information is stored as part of a management information base of the reference network device.

24. A network device comprising:

an input interface configured to obtain a geographical location associated with the network device;

a processing circuit coupled to the input interface and configured to obtain the geographical location from the interface, store the geographical location and support a network time protocol that facilitates distance estimation between the reference network device and one or more other network devices by synchronizing their clocks; and

an output interface coupled to the processing circuit to transmit the geographical location to at least one of the one or more other network devices for determining a geographical location of the at least one of the one or more other network devices using packet exchanges based on the clock synchronization,

wherein a mechanism is provided to selectively identify and authenticate the network device as being authorized to act as a reference network device to the at least one of the one or more other network devices.

25. The network device of claim 24, wherein the processing circuit is further configured to automatically propagate the geographical information to the at least one of the one or more other network devices via the output interface.

26. The network device of claim 24, wherein the processing circuit is further configured to monitor for changes in the geographical location of the network device.

27. The network device of claim 24, wherein the input interface is coupled to one of either an internal geolocation device, an external geolocation device, or a user input device for manual entry of geolocation information.

28. The network device of claim 24, wherein the geographical location of the network device is obtained by:

acquiring one or more reference geographical locations for other network reference devices;

determining one or more distances from the network device to each of the other network reference devices; and

deriving the geographical location of the network device based on the one or more reference geographical locations of the other network reference devices and the one or more distances.

29. The network device of claim 24, wherein the input interface is a local interface to couple directly to a reference infrastructure device to obtain a reference geographical location.

30. The network device of claim 29, wherein a transmission medium to the reference infrastructure device and a propagation speed of the transmission medium are determined.

31. The network infrastructure device of claim 30, wherein the transmission medium propagation speed is used to obtain a propagation time to the reference infrastructure device and the geographical location associated with the network device is obtained based on the reference geographical location and the propagation time to the reference infrastructure device.

32. The network device of claim 29, further comprising:

a first clock to synchronize with a second clock in the reference infrastructure device, the synchronized first and second clocks facilitating a direct one-way trip time measurement between the network device and the reference infrastructure device.

33. The network device of claim 32, wherein the direct one-way trip time measurement is performed for both a transmit path from the network device and a receive path to the network device.

34. The network infrastructure device of claim 33, wherein the transmit path has a different transmission speed than the receive path.

35. The network device of claim 24, wherein the processing circuit is further configured to:

include an indication of a level of accuracy of the geographical location in the geographical location of the reference network device, wherein the level of accuracy indicates a number of hops on the communication network that the reference network device is located from a source device with a geographic location information having a highest level of accuracy; and

transmit the level of accuracy of the geographical location along with the geographical location.

36. An apparatus, comprising:

means for obtaining a geographical location of a reference network device;

means for storing the geographical location; and

means for supporting a network time protocol that facilitates distance estimation between the reference network device and one or more other network devices by synchronizing their clocks; and

wherein the geographical location is provided to at least one of the one or more other network devices for determining a geographical location of the at least one of the one or more other network devices using packet exchanges based on the clock synchronization; and

wherein a mechanism is provided to selectively identify and authenticate at least one network device as being authorized to act as the reference network device to the at least one of the one or more other network devices.

37. The apparatus of claim 36, further comprising:

means for monitoring for a change in the geographical location of the reference network device.

38. A non-transitory machine-readable storage medium having one or more instructions for enabling a network device to facilitate propagation of geographical location information, which when executed by a processor causes the processor to:

obtain a reference geographical location associated with a second network device;

synchronize a first clock in the network device with a second clock in the second network device, the synchronized first and second clocks facilitating a direct one-way trip time measurement between the network device and the second network device;

obtain a one-way distance between the network device and the second network device based on the direct one-way trip time measurement using packet exchanges;

obtain a geographical location associated with the network device based on the reference geographical location and the one-way distance; and

provide the geographical location to a third network device to enable the third network device to obtain its own geographical location, wherein a mechanism is provided to selectively identify and authenticate the network device as being authorized to act as a reference network device to the third network device.

39. The non-transitory machine-readable storage medium of claim 38, further comprising one or more instructions to:

acquire one or more reference geographical locations for other network infrastructure devices;

determine one or more distances from the network device to each of the one or more reference geographical locations; and

derive the geographical location of the network device based on the one or more reference geographical locations of the other network devices and the one or more distances.

40. The non-transitory machine-readable storage medium of claim 38, further comprising one or more instructions being further executable by the processor to:

include an indication of a level of accuracy of the geographical location in the geographical location, wherein the level of accuracy indicates a number of hops on the communication network that the reference network device is located from a source device with a geographic location information having a highest level of accuracy; and

provide the level of accuracy of the geographical location along with the geographical location.

41. The non-transitory machine-readable storage medium of claim 40, wherein the level of accuracy of the geographical location is determined based on one or more level of accuracy associated with one or more reference geographical locations for other network devices.

42. The non-transitory machine-readable storage medium of claim 40, further comprising one or more instructions to update the geographical location of the network device based on one or more new reference geographical locations for other network devices having associated level of accuracy, wherein the network device uses a particular reference geographical location only if its associated level of accuracy is better than the level of accuracy associated with the network device.

43. The non-transitory machine-readable storage medium of claim 38, further comprising one or more instructions to append an expiration timestamp to the geographical location provided to other network devices, wherein the expiration timestamp indicates how long the geographical location can be relied on.

44. A method for disseminating geographical location information across a communication network, comprising:

providing a reference geographical location from a reference network device to other network devices, wherein a mechanism is provided to identify and authenticate at a first network device of the other network devices as being authorized to request the reference geographical location;

synchronizing clocks between the reference network device and the first network device to facilitate a one-way trip time measurement between the reference network device and the first network device;

obtaining a distance between the reference network device and the first network device based on the one-way trip time measurement using packet exchanges occurring over the transmission lines; and

obtaining a geographical location for the first network device based on the reference geographical location and the distance between the reference network device and the first network device.

45. The method of claim 44, further comprising:

compensating for time delays caused by intervening network devices between the reference network device and the first network device to enhance the accuracy of the distance between the reference network device and the first network device.

46. The method of claim 44, further comprising:

obtaining a roundtrip time measurement between the reference network device and a non-synchronized network infrastructure device;

ascertaining processing delays at the non-synchronized network infrastructure device;

obtaining a distance between the reference network device and the non-synchronized network infrastructure device based on the roundtrip time measurement and compensating for the processing delays; and

obtaining a geographical location for the non-synchronized network infrastructure device based on the reference geographical location and the distance between the reference network device and the non-synchronized network infrastructure device.

47. A non-transitory machine-readable storage medium having one or more instructions which when executed by a processor causes the processor to:

obtain a geographical location of a reference network device;

store the geographical location; and

support a network time protocol that facilitates distance estimation between the reference network device and one or more other network devices by synchronizing their clocks;

wherein the geographical location is provided to at least one of the one or more other network devices for determining a geographical location of the at least one of the one or more other network devices using packet exchanges based on the clock synchronization; and

wherein a mechanism is provided to selectively identify and authenticate at least one network device as being authorized to act as the reference network device to the at least one of the one or more other network devices.