Patent ID: 7697509

Claim:
A method comprising the steps of: (a) establishing a location database for a first network that associates Internet Protocol address information for Voice over Internet Protocol (VOIP) telephony devices with physical locations for the VOIP telephony devices; (b) upon detecting registration of a VOIP telephony device through a network port of the first network, determining physical location of the VOIP telephony device by identifying physical location of the network port through which the VOIP telephony device is connected, and updating the location database, wherein determining the physical location of the network port through which the VOIP telephony device is connected comprises i) sending an Internet Control Message (ICMP) Protocol Ping message to the VOIP telephony device, ii) comparing a present Internet Protocol (IP) address to a last known IP address, and iii) upon determining that the present IP address is the same as the last known IP address, sending a Simple Network Management Protocol (SNMP) query to the last known connection port to determine if the VOIP telephony device is located on a different port of a same device; and (c) upon detecting IP telephony activity originating from a remote VOIP telephony device connected to the first network through a virtual private network (VPN) gateway, determining physical location of the remote VOIP telephony device connected through the VPN gateway by identifying physical locations of network resources of a second network to which the remote VOIP telephony device is connected, and updating the location database; such that updated location information is provided to a 911 server in the event that an emergency call is originated by any one of a VOIP telephony device and remote VOIP telephony device.