METHOD AND SYSTEM FOR PROVIDING LOCATION INFORMATION OF TARGET DEVICE

1 . A method of providing a location of a target device to an application implementing a location based service, the method comprising:

receiving a request for a location reference from the target device at a first location server;

generating the location reference in response to the request, an external domain to which the location reference is attributed corresponding to a second location server different from the first location server;

providing the location reference to the target device, the target device providing the location reference to the application, which subsequently requests the location of the target device from the second location server using the location reference;

receiving a query from the second location server requesting the location of the target device, the query including the location reference; and

identifying the target device using the location reference.

2 . The method of claim 1 , further comprising:

determining the location of the target device in response to the query.

3 . The method of claim 2 , further comprising:

providing the determined location of the target device to the second location server, which provides the determined location to the application.

4 . The method of claim 1 , wherein the location reference comprises a uniform resource identifier (URI).

5 . The method of claim 4 , wherein the first location server has no preexisting trust relationship with the application, and the second location server has a preexisting trust relationship with the application.

6 . The method of claim 5 , wherein the first location server comprises an asserting location information server (LIS) and the second location server comprises a validating LIS.

7 . The method of claim 5 , wherein the application comprises an Internet application.

8 . The method of claim 7 , wherein the Internet application comprises a public safety access point (PSAP) associated with an emergency call center for answering calls to emergency numbers.

9 . A method of providing a location of a target device to an application implementing a location based service, the method comprising:

receiving a request for a location of the target device from the application at a second location server, the request including a location reference identifying the target device and a first location server that generated the location reference;

querying the first location server identified in the location reference for the location of the target device, the first location server determining the location of the target device identified in the location reference;

receiving the determined location of the target device from the first location server; and

providing the determined location of the target device to the application.

10 . The method of claim 9 , wherein the location reference comprises a uniform resource identifier (URI).

11 . The method of claim 10 , wherein an external domain to which the location URI is attributed corresponds to the second location server.

12 . The method of claim 9 , further comprising:

validating the determined location of the target device before providing the determined location to the application.

13 . The method of claim 12 , wherein validating the determined location of the target device comprises:

comparing the determined location to known boundaries of a first network that includes the first location server; and

verifying the determined location of the target device with the determined location is within the known boundaries.

14 . The method of claim 13 , further comprising:

generating an alternative location of the first location server when the determined location of the target device is not within the known boundaries.

15 . The method of claim 13 , further comprising:

querying the first location server again for the location of the target device when the determined location of the target device is not within the known boundaries.

16 . The method of claim 11 , wherein the first location server has no preexisting trust relationship with the application, and the second location server has a preexisting trust relationship with the application.

17 . The method of claim 9 , wherein the application comprises a public safety access point (PSAP) associated with an emergency call center for answering calls to emergency numbers.

18 . A system for retrieving a location of a target device, the system comprising:

an asserting location information server (LIS) in an enterprise network, the asserting LIS providing a location uniform resource identifier (URI) to a target device in the enterprise network, the target device sending the location URI to an Internet application providing a location based service to the target device, wherein the location URI points to a validating LIS and includes parameters that identify the target device and the asserting LIS, respectively; and

the validating LIS in a carrier network, the validating LIS receiving the location URI from the Internet application in a request for the location of the target device, identifying the asserting LIS using the corresponding identification parameter in the location URI, providing the location URI in a request to the asserting LIS for the location of the target device, receiving the location of the target device from the asserting LIS, and providing the received location of the target device to the Internet application,

wherein the asserting LIS does not have a trust relationship with the Internet application.

19 . The system of claim 18 , wherein the asserting LIS further identifies the target device using the corresponding identification parameter in the location URI and determines the location of the target device in response to the request from the validating LIS.

20 . The system of claim 19 , wherein the validating LIS further verifies the received location of the target device before providing the received location of the target device to the Internet application.