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SYSTEM, METHOD AND APPARATUS FOR SUPPORTING E911 EMERGENCY SERVICES IN A DATA COMMUNICATIONS NETWORK
BACKGROUND OF THE INVENTION 5
1. Field of the Invention
The present invention is generally directed to Voice over Internet Protocol (VoIP) telephony. In particular, the present invention is directed to supporting enhanced 911 (E911) 10 emergency services in a data communications network that includes VoIP telephones.
2. Background
Internet Protocol (IP) telephony is an important part of the convergence of data, voice and broadband services into a 15 single integrated information environment. Voice over Internet Protocol (VoIP) refers to an organized effort to standardize IP telephony and is a term used in IP telephony for a set of facilities for managing the delivery of voice information using the Internet Protocol. In IP telephony, voice informa- 20 tion is transmitted in discrete packets over shared bandwidth, rather than over the traditional circuit driven protocol used by the traditional Public Switched Telephone Network (PSTN). The goal of VoIP is to use the Internet environment, which was not designed to provide traditional "toll" Quality 25 of Service (QoS) for telephony, to provide the same high quality voice transmission that the traditional PSTN currently enjoys. IP telephony service providers include, or soon will include, local telephone companies, long distance providers, cable TV companies, Internet service providers 30 (ISPs), wireless service providers and fixed wireless local loop service operators.
As VoIP efforts progress, the first VoIP telephones are becoming commercially available. VoIP telephones offer flexibility not available in traditional plain old telephones 35 (POTS). For instance, like a laptop computer, a VoIP telephone can be easily moved from one point of network access to another without the assistance of a telephony administrator, and without having to change its identifying characteristics. Such identifying characteristics may include a tele- 40 phone number, an IP address, and/or a media access control (MAC) address. While such ease of access may be desirable from an end user perspective, it creates significant concerns from the perspective of providing mission critical services such as enhanced emergency services, also known as E911. 45
The 3-digit telephone number 9-1-1 has been designated for public use throughout the United States and Canada to report an emergency, request emergency assistance, or both. By dialing 9-1-1, a person is provided direct access to a Public Safety Answering Point (PSAP). A PSAP is an 50 agency or group of agencies designated and authorized to receive and respond to emergency calls requiring one or more public services, such as Police, Fire or Emergency Medical Service. Because the 9-1-1 number does not change, and there are thousands of PSAP's in the United 55 States and Canada, it is vital that 9-1-1 calls are routed to the appropriate PSAP—i.e., the one closest to the location where the call originates. Traditionally, before the advent of mobile telephones, a telephony administrator, normally working for the local telephony service provider, automati- 60 cally routed calls from a fixed telephone to the nearest PSAP. Because a telephony administrator was required to move a user's extension from one location to another, the administrator could also ensure proper routing of 9-1-1 calls.
With the advent of mobile telephones, a new system was 65 necessary. This led to the advent of enhanced emergency services, or enhanced 911 (E911). The main characteristic of
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E911 service is the capability to selectively route a 9-1-1 call originating from any device (mobile and fixed alike) in the E911 service area to the correct PSAP designated to serve the originating devices' location. Another key feature of E911 is that it also provides the PSAP operator with the location of the calling device and a callback number. These enhanced features are implemented primarily through the use of Selective Routing (SR), and maintenance of an Automatic Location Identification (ALI) database. Selective Routing refers to the routing of a 9-1-1 call to the proper PSAP based upon the location of the caller. The ALI database, which is regularly updated to match telephone numbers to physical locations, works within a database management system to automatically provide the PSAP operator the physical location of the calling device and a callback number.
The ability to support E911 services is mandated in many states. In a VoIP environment, it is possible for a user to successfully move their IP phone from one network access point to another without notifying the telephony administrator. In this case, the telephony administrator would be unable to update the ALI database with the new location of the user and as a result, the ALI database would not contain the new location of that user. The ability to provide physical location information to update E911 service database is available for VoIP deployment, but conventional solutions are proprietary, and require the user to choose the same vendor to provide, upgrade, and replace key system components. The concern with this approach is that it does not allow users to take advantage of industry innovations. Instead, customers are forced to rely on products from a single vendor.
It would be beneficial, then, to provide integration between a network infrastructure for E911 services and VoIP telephones that is based on industry standards, rather than proprietary technologies. It would also be beneficial to provide a system, method and apparatus for supporting E911 emergency services in a data communications network by automatically updating an ALI database each time a user changes the location of a VoIP telephone within the network.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to a network system, method and apparatus that substantially obviates one or more of the problems and disadvantages of the related art. In particular, the present invention is directed to a system, method and apparatus for supporting enhanced 911 (E911) emergency services in a data communications network by facilitating the identification of a physical location of a VoIP telephone.
A method of supporting E911 emergency services in a network access device in accordance with an embodiment of the present invention includes assigning a physical location identifier to an input port of the network access device, detecting a Voice over Internet Protocol (VoIP) telephone coupled to the input port, authenticating the VoIP telephone, wherein authenticating includes receiving a unique device identifier from the VoIP telephone, and transmitting the unique device identifier and the physical location identifier to an E911 database management system. This method permits the E911 database management system to store the physical location identifier in association with the unique device identifier. Preferably, the authentication of the VoIP telephone is performed in accordance with an industryrecognized protocol, such as IEEE 802. lx.
An embodiment of the present invention also includes a network access device that supports E911 emergency services. The device includes an input port, a switching fabric for routing data received via the input port to at least one output port, and control logic. The control logic is adapted 5 to assign a physical location identifier to the input port, to authenticate a VoIP telephone when the VoIP telephone is coupled to the input port, wherein the authentication includes receiving a unique device identifier from the VoIP telephone, and to transmit the unique device identifier with 10 the physical location identifier to an E911 database management system. This permits the E911 database management system to store the physical location identifier in association with the unique device identifier. Preferably, the authentication of the VoIP telephone is performed in accor- 15 dance with an industry-recognized protocol, such as IEEE 802. lx.
An embodiment of the present invention further includes a network system for supporting E911 emergency services. The network system includes a host network, a network 20 access device, and a VoIP telephone. The host network is communicatively coupled to an E911 database management system. The network access device is communicatively coupled to the host network. The VoIP telephone is communicatively coupled to an input port of the network access 25 device. The network access device is adapted to assign a physical location identifier to the input port, to authenticate the VoIP telephone, wherein the authentication includes receiving a unique device identifier from the VoIP telephone, and to transmit the location identifier and the unique device identifier to the E911 database management system. This permits the E911 database management system to store the physical location identifier in association with the unique device identifier. Preferably, the authentication of the VoIP telephone is performed in accordance with an industryrecognized protocol, such as IEEE 802.lx.
Yet another embodiment of the invention includes a method of supporting enhanced 911 (E911) emergency services that leverages an industry standard management 4Q information protocol. The method includes assigning a physical location identifier to an input port of a network access device. The network access device transmits an automatic report to an E911 database management system (DBMS) when a user device is coupled to the input port. 45 Next, the network access device transmits a unique device identifier of the user device to the E911 DBMS in response to an identification query from the E911 DBMS. If the user device is a VoIP telephone, then the network access device transmits the physical location identifier to the E911 DBMS 5Q in response to a physical location query from the E911 DBMS. The above method allows the E911 DBMS to automatically update an automatic location identification database with the physical location of the VoIP telephone.
Embodiments of the present invention are an improve- 55 ment over conventional solutions because they provide a standards-based manner for complying with E911 requirements that avoids reliance on proprietary technology.
Further features and advantages of the invention, as well as the structure and operation of various embodiments of the 60 invention, are described in detail below with reference to the accompanying drawings. It is noted that the invention is not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to persons 65 skilled in the relevant art(s) based on the teachings contained herein.
BRIEF DESCRIPTION OF THE
DRAWINGS/FIGURES
The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the relevant art(s) to make and use the invention.
FIG. 1 depicts the basic elements of a data communications system in accordance with an embodiment of the present invention.
FIG. 2 depicts an exemplary high-level architecture of a network access device in accordance with an embodiment of the present invention
FIG. 3 depicts an exemplary high-level architecture of a Voice over Internet Protocol (VoIP) telephone in accordance with an embodiment of the present invention.
FIG. 4 is a flowchart describing a method for supporting enhanced 911 (E911) emergency services in a data communications network that includes VoIP telephones in accordance with an embodiment of the present invention.
FIGS. 5A and 5B are flowcharts describing a method for supporting E911 emergency services in a data communications network that includes a VoIP telephone, a network access device, and an E911 database management system that support an industry standard management information protocol in accordance with an embodiment of the present invention.
The features and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawings in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.
DETAILED DESCRIPTION OF THE
INVENTION
A. Overview
The present invention provides a system, method and apparatus for supporting enhanced 911 (E911) emergency services in a data communications network that includes Voice over Internet Protocol (VoIP) telephones, by facilitating the identification of a physical location of a VoIP telephone. An embodiment of the invention allows a host network to comply with E911 requirements using a standards-based approach that is independent of proprietary technologies used by the host network. Specifically, information obtained from a VoIP telephone by a network access device during execution of a standard user authentication protocol is coupled with port location information to automatically update an Automatic Location Information (ALI) database of the E911 vendor. Such an automatic update provides comprehensive location details for each VoIP telephone connected to the host network. In a preferred embodiment, information obtained during execution of a user authentication protocol in accordance with the IEEE 802. lx standard is used to comply with E911 requirements.
An alternate embodiment allows a host network to comply with E911 requirements using an industry standard protocol that facilitates the automatic exchange of management information between network devices. Preferably, the
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