Patent ID: 8200240

Claim:
A method comprising: a mobile location server sending to a mobile client device a first location-determination message that designates as an origination address of the first location-determination message a network address of the mobile location server, wherein the network address of the mobile location server is an Internet Protocol (IP) address of the mobile location server; the mobile location server then detecting that the mobile client device has not responded to the sent first location-determination message, wherein detecting that the mobile client device has not responded to the sent first location-determination message comprises detecting an absence of a responsive IP communication from the mobile client device; responsive to the detecting, the mobile location server causing a trusted server to send to the mobile client device a second location-determination message that designates as an origination address of the second location-determination message a network address of the trusted server and that directs the mobile client device to send a response to the mobile location server, to facilitate determination of a geographic location of the mobile client device, wherein the trusted server is other than the mobile location server; and the mobile location server then receiving the response.