Abstract:
A system receives a Voice over Internet Protocol (VoIP) 9-1-1 call and Global Positioning Satellite (GPS) data from a first network device and identifies a Public Safety Answering Point (PSAP) using the received GPS data.

Description:
FIELD OF THE INVENTION 
     Implementations consistent with the principles of the invention relate generally to communications networks and, more particularly, to routing Voice over Internet Protocol (VoIP) emergency 9-1-1 calls. 
     BACKGROUND OF THE INVENTION 
     The United States 9-1-1 wireline infrastructure is designed to automatically route Public Switched Telephone Network (PSTN) based 9-1-1 calls to designated geographic Public Safety Answering Points (PSAPs) based upon the ten digit Automatic Number Identification (ANI) of the 9-1-1 caller. The PSAP then confirms the address of the 9-1-1 caller by using the ANI to query subscriber area location information maintained in a local exchange carrier (LEC)-owned distributed database network. This database is updated by the LEC based upon service address information provided by subscribers. Emergency services dispatch can then be made (in instances when the caller cannot assist and/or verbally relay location information) to the registered address of the caller. 
     Updates have been made to the 9-1-1 wireline infrastructure to handle wireless 9-1-1 calls. Wireless calls are routed to the correct PSAP based on cell identification (ID) information and/or pseudo ten digit ANIs that are generated by third party providers. The PSAP determines caller location by either referencing cell ID-based information or the address associated with the latitude/longitude of the caller provided by the cellular carrier. In both cases area location identification information can be referenced by the PSAP (if the caller cannot assist in providing location information) to assist dispatch, but this may often be inaccurate due to the nomadic nature of cellular service. 
     Internet telephony, such as Voice over IP (VoIP) phone service, is reportedly poised to become the predominant technology used in the telecommunications industry. Thus, emergency calls will increasingly be placed from VoIP devices. Neither the wireline 9-1-1 infrastructure nor the updated wireless 9-1-1 infrastructure can automatically route VoIP calls to the geographically closest PSAP on a reliable basis. Moreover, even in the case where correct PSAP routing can be made, the 9-1-1 caller&#39;s area location identification information will very often be incorrect and cannot be used to assist dispatch in those situations where the caller cannot verbally relay information. 
     SUMMARY OF THE INVENTION 
     In an implementation consistent with the principles of the invention, a system includes a first network device that is configured to detect placement of a VoIP 9-1-1 call, capture current Global Positioning Satellite (GPS) data in response to the detecting, and transmit the GPS data and 9-1-1 digits. 
     In another implementation consistent with the principles of the invention, a method includes receiving a VoIP 9-1-1 call and GPS data from a first network device and identifying a PSAP using the received GPS data. 
     In still another implementation consistent with the principles of the invention, a system includes a first network device. The first network device is configured to periodically capture GPS data when the first network device is connected to a network, and transmit the captured GPS data and information identifying the first network device to a second network device. 
     In yet another implementation consistent with the principles of the invention, a method includes detecting, via a first device, a placing of a VoIP 9-1-1 call; obtaining, via the first device, GPS data in response to the detecting; transmitting the GPS data, information identifying the first device, and information identifying the VoIP 9-1-1 call as a 9-1-1 call to a second device; identifying, via the second device, a PSAP based on the GPS data; and forwarding the VoIP 9-1-1 call and location information relating to the GPS data to the identified PSAP. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, explain the invention. In the drawings, 
         FIG. 1  illustrates an exemplary system in which systems and methods, consistent with the principles of the invention, may be implemented; 
         FIG. 2  illustrates an exemplary configuration of the user device of  FIG. 1  in an implementation consistent with the principles of the invention; 
         FIG. 3  illustrates an exemplary configuration of the 9-1-1 service provider of  FIG. 1  in an implementation consistent with the principles of the invention; 
         FIG. 4  illustrates an exemplary configuration of the PSAP of  FIG. 1  in an implementation consistent with the principles of the invention; 
         FIG. 5  illustrates an exemplary configuration of the Automatic Location Identification (ALI) device of  FIG. 1  in an implementation consistent with the principles of the invention; 
         FIG. 6  illustrates an exemplary process for handling a VoIP 9-1-1 call in an implementation consistent with the principles of the invention; 
         FIG. 7  illustrates exemplary processing of a VoIP 9-1-1 call in an implementation consistent with the principles of the invention; and 
         FIG. 8  illustrates an exemplary process for updating an ALI device with current location information for a user device in an implementation consistent with the principles of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description of implementations consistent with the principles of the invention refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims and their equivalents. 
     Implementations consistent with the principles of the invention use GPS coordinates from a user device for routing a 9-1-1 call from the user device to the appropriate PSAP. In one implementation, the GPS coordinates are provided from a GPS device that is associated with the user device. Implementations consistent with the principles of the invention also allow for periodic updates of Automatic Location Identification (ALI) information for user devices. 
     Exemplary System 
       FIG. 1  illustrates an exemplary system  100  in which systems and methods, consistent with the principles of the invention, may be implemented. As illustrated, system  100  may include a user device  130  that connects to a 9-1-1 service provider (SP)  140  via a network  110 . 9-1-1 service provider  140  may connect to a PSAP  150  and an ALI device  160  via a network  120 . The number of user devices, 9-1-1 service providers, PSAPs, ALI devices, and networks illustrated in  FIG. 1  is provided for simplicity. In practice, a typical system could include more or fewer user devices, 9-1-1 service providers, PSAPs, ALI devices, and networks than illustrated in  FIG. 1 . 
     Networks  110  and  120  may include a local area network (LAN), a wide area network (WAN), a telephone network, such as the Public Switched Telephone Network (PSTN), an intranet, the Internet, or a combination of these or other networks. Although shown as separate networks, networks  110  and  120  may, in one implementation consistent with the principles of the invention, be implemented as a single network. 
     User device  130  may include a device, such as a personal computer, a lap top, a personal digital assistant (PDA), a wireless telephone, an Internet Protocol (IP) telephone, etc., one or more threads or processes running on these devices or other types of devices, and/or one or more objects executable by these devices. In one implementation, user device  130  may allow a user to place calls, including 9-1-1 emergency calls, using VoIP. User device  130  may connect to network  110  via any technique, such as wired, wireless, or optical connections. 
     9-1-1 service provider  140  may include one or more types of computer systems, such as a mainframe, minicomputer, or personal computer. 9-1-1 service provider  140  may facilitate the establishment of VoIP 9-1-1 calls between user device  130  and PSAP  150 . In one implementation consistent with the principles of the invention, 9-1-1 service provider  140  may be associated with a VoIP provider, network service provider, or another party. 9-1-1 service provider  140  may connect to networks  110  and  120  via any technique, such as wired, wireless, or optical connections. 
     PSAP  150  can include one or more devices for receiving and processing emergency calls (e.g., 9-1-1 calls). For example, PSAP  150  may include a public entity having personnel (e.g., operators or call takers) and/or equipment for initially answering or fielding incoming 9-1-1 calls. PSAP  150  can be located in the vicinity of the source of the emergency call and in the vicinity of emergency service providers to which the call can be forwarded. PSAP  150  may connect to network  120  via any technique, such as wired, wireless, or optical connections. 
     ALI device  160  may include one or more devices that store location information for a user device  130  from which a 9-1-1 call can be placed. In one implementation consistent with the principles of the invention, ALI device  160  may include a database system. ALI device  160  may connect to network  120  via any technique, such as wired, wireless, or optical connections. 
     Exemplary User Device Configuration 
       FIG. 2  illustrates an exemplary configuration of user device  130  in an implementation consistent with the principles of the invention. As illustrated, user device  130  may include a bus  210 , processing logic  220 , a memory  230 , an input device  240 , an output device  250 , a GPS device  260 , and a communication interface  270 . It will be appreciated that user device  130  may include other components (not shown) that aid in receiving, transmitting, and/or processing data. Moreover, it will be appreciated that other configurations are possible. 
     Bus  210  may permit communication among the components of user device  130 . Processing logic  220  may include any type of processor or microprocessor that interprets and executes instructions. In other implementations, processing logic  220  may be implemented as or include an application specific integrated circuit (ASIC), field programmable gate array (FPGA), or the like. Memory  230  may include a random access memory (RAM) or another type of dynamic storage device that stores information and instructions for execution by processing logic  220 , a read only memory (ROM) or another type of static storage device that stores static information and instructions for the processing logic  220 , and/or some other type of magnetic or optical recording medium and its corresponding drive for storing information and/or instructions. 
     Input device  240  may include a device that permits a user to input information to user device  130 , such as a keyboard, a keypad, a mouse, a pen, a microphone, one or more biometric mechanisms, and the like. Output device  250  may include a device that outputs information to the user, such as a display, a printer, a speaker, etc. 
     GPS device  260  may include one or more devices for receiving GPS-based location information from, for example, a GPS satellite. GPS device  260  may be included within user device  130  or external to user device  130 . For example, GPS device  260  may be implemented as an external GPS receiver or a Personal Computer Memory Card International Association (PCMCIA) card with integral GPS receiver that continuously receives GPS-based location information. GPS device  260  may store received GPS-based location information in, for example, memory  230 , GPS device  260 , or some other location. 
     Communication interface  270  may include any transceiver-like mechanism that enables user device  130  to communicate with other devices and/or systems. For example, communication interface  270  may include mechanisms for communicating with 9-1-1 service provider  140  via a network, such as network  110 . 
     As will be described in detail below, user device  130 , consistent with the principles of the invention, may allow a user to place a VoIP emergency 9-1-1 call. User device  130  may perform these and other functions in response to processing logic  220  executing software instructions contained in a computer-readable medium, such as memory  230 . A computer-readable medium may be defined as one or more memory devices and/or carrier waves. The software instructions may be read into memory  230  from another computer-readable medium or from another device via communication interface  270 . The software instructions contained in memory  230  may cause processing logic  220  to perform processes that will be described later. Alternatively, hardwired circuitry may be used in place of or in combination with software instructions to implement processes consistent with the principles of the invention. Thus, systems and methods consistent with the principles of the invention are not limited to any specific combination of hardware circuitry and software. 
     Exemplary 9-1-1 Service Provider Configuration 
       FIG. 3  illustrates an exemplary configuration of 9-1-1 service provider  140  in an implementation consistent with the principles of the invention. As illustrated, 9-1-1 service provider  140  may include a VoIP 9-1-1 call routing device  310  and an ALI update device  320 . It will be appreciated that 9-1-1 service provider  140  may include other components (not shown) that aid in receiving, transmitting, and/or processing data. 
     VoIP 9-1-1 call routing device  310  may include one or more devices that receive 9-1-1 emergency information from user device  130 , identify an appropriate PSAP, such as PSAP  150 , for handling the 9-1-1 call, and transmit the appropriate information to PSAP  150  for handling the 9-1-1 call. VoIP 9-1-1 call routing device  310  may be implemented in hardware, software, or a combination of hardware and software. 
     ALI update device  320  may include one or more device for receiving GPS-based location information from user device  130  and updating ALI device  160  based on the received GPS-based location information. In this way, ALI update device  320  may ensure that ALI device  160  contains the most recent location information for the user associated with user device  130 . ALI update device  320  may be implemented in hardware, software, or a combination of hardware and software. 
     Exemplary PSAP Configuration 
       FIG. 4  illustrates an exemplary configuration of PSAP  150  in an implementation consistent with the principles of the invention. As illustrated, PSAP  150  may include an ALI controller  410 , a workstation  420 , and a telephone  430 . It will be appreciated that PSAP  150  may include other components than illustrated in  FIG. 4  that aid in receiving, processing, and/or transmitting data. The number of ALI controllers, workstations, and telephones illustrated in  FIG. 4  is provided for simplicity. In practice, a typical PSAP could include more ALI controllers, workstations, and/or telephones than illustrated in  FIG. 4 . 
     ALI controller  410  may include one or more devices that receive emergency 9-1-1 information from 9-1-1 service provider  140  and process the received emergency 9-1-1 information by, for example, identifying the location from where the call originates. In one implementation consistent with the principles of the invention, ALI controller  410  may identify a caller&#39;s location based on GPS-based location information received with the 9-1-1 emergency call. ALI controller  410  may, alternatively, retrieve caller location information from ALI device  160  and verify the location information using the GPS-based location information received with the 9-1-1 call. 
     Workstation  420  may include one or more types of computer systems, such as a mainframe, minicomputer, a personal computer, a lap top, etc. that receive emergency 9-1-1 information and provide information to an operator in response thereto. The information may include, for example, a callback number (e.g., a telephone number, a network address, etc.) and information identifying a location of the person placing the 9-1-1 call. Workstation  420  may, in some situations, forward received calls to an appropriate emergency personnel service, such as a fire department, a police station, etc. 
     Telephone  430  may include one or more devices that allow an operator at PSAP  150  to conduct voice communications with the person placing the 9-1-1 call. In one implementation consistent with the principles of the invention, telephone  430  may include a plain old telephone system (POTS) telephone, a session initiation protocol (SIP) telephone, a wireless telephone device, etc. In another implementation, telephone  430  may be implemented within workstation  420  or another computer device. 
     Exemplary Configuration of ALI Device 
       FIG. 5  illustrates an exemplary configuration of ALI device  160  in an implementation consistent with the principles of the invention. As illustrated, ALI device  160  may include a database  510  that stores location information for different ANIs. While only one database is described below, it will be appreciated that database  510  may consist of multiple databases stored at, for example, PSAP  150 , or stored at one or more locations throughout network  120 . 
     In one implementation consistent with the principles of the invention, database  510  may include a group of entries in the following exemplary fields: ANI field  520  and location information field  530 . Database  510  may contain additional fields (not shown) that aid in identifying a location of a 9-1-1 caller. 
     ANI field  520  may store user device identifiers for user devices  130  in system  100 . For example, the identifiers may include a telephone number, a network address, etc. 
     Location information field  530  may store location information for each identifier in ANI field  520 . The location information may be stored as latitude/longitude coordinates, street addresses, etc. In one implementation consistent with the principles of the invention, the location information may be used by an operator at PSAP  150  for determining a location of a 9-1-1 caller or for verifying a location of a 9-1-1 caller. 
     Exemplary Processing 
       FIG. 6  illustrates an exemplary process for handling a VoIP 9-1-1 call in an implementation consistent with the principles of the invention. Processing may begin with a user placing a VoIP 9-1-1 call at a user device, such as user device  130  (act  610 ). To place the 9-1-1 call, the user may simply dial 9-1-1 using user device  130 . In response, user device  130  may capture current GPS data (act  610 ), using, for example, GPS device  260 . If user device  130  is unable to capture current GPS data, user device  130  may retrieve the most recently captured GPS data from, for example, memory  230 . 
     User device  130  may transmit information to 9-1-1 service provider  140  (act  620 ). The information may include, for example, the dialed digits (i.e., 9-1-1), ANI information for user device  130  (e.g., a telephone number associated with user device  130 ), and the captured (or most recently) GPS data. 
     In response to receiving the information from user device  130 , 9-1-1 service provider  140  may use the GPS data to identify a PSAP to which to direct the 9-1-1 call (act  630 ). In one implementation consistent with the principles of the invention, 9-1-1 service provider  140  may use the GPS data to determine the location of user device  130 . 9-1-1 service provider  140  may then identify a PSAP that is geographically closest to the location of user device  130 . It is assumed for explanatory purposes that 9-1-1 service provider  140  identifies PSAP  150  as the geographically closest PSAP to the location of user device  130 . 
     9-1-1 service provider  140  may obtain a pseudo ANI (pANI) for PSAP  150  (act  640 ). In one implementation consistent with the principles of the invention, the pANI, like a telephone number, may include a 10-digit number that cannot be assigned to a user device  130 . Network  120  may use the pANI to route the 9-1-1 call from user device  130  to the appropriate PSAP (i.e., PSAP  150  in the example above). In one implementation, 9-1-1 service provider  140  may select an appropriate pANI from a group of available pANIs. 
     In those situations when PSAP  150  is capable of processing Phase I or Phase II wireless 9-1-1 calls, 9-1-1 service provider  140  may convert the received GPS data to a format that PSAP  150  may process (act  650 ). For example, if PSAP  150  is capable of processing Phase II wireless 9-1-1 calls, 9-1-1 service provider  140  may convert the GPS data (if necessary) to latitude and longitude coordinates and transmit these coordinates to PSAP  150  as a Phase II-formatted message. PSAP  150  may, for example, use this location information to verify the accuracy of the caller&#39;s location information in ALI device  160 . This will allow PSAP  150  to avoid instances where the delay cycle associated with updating ALI device  160  renders the caller&#39;s ALI information useless. 
     9-1-1 service provider  140  may forward the formatted location information and the 9-1-1 call to PSAP  150  (act  660 ). As indicated above, the forwarding of the 9-1-1 call to PSAP  150  may be based on the pANI obtained by 9-1-1 service provider  140 . PSAP  150  may then process the 9-1-1 call from user device  130  by, for example, dispatching the appropriate emergency services personnel to the location of user device  130 . 
     9-1-1 service provider  140  may also update ALI device  160  based on the GPS data received from user device  130  (act  670 ). In one implementation consistent with the principles of the invention, 9-1-1 service provider  140  may, for example, forward the ANI and GPS data received from user device  130  to ALI device  160 . ALI device  160  may lookup the ANI in, for example, database  510  and replace any existing location data in field  530  with the GPS data. If necessary, 9-1-1 service provider  140  or ALI device  160  may convert the GPS data into a desired format prior to storing the location information in database  510 . For example, 9-1-1 service provider  140  or ALI device  160  may convert the GPS data to a physical address (e.g., street and city) prior to storing the location information. 9-1-1 service provider  140  may update ALI device  160  with the current location of user device  130  prior to, in parallel with, or subsequent to providing the information described above with respect to act  660  to PSAP  150 . 
     The following example illustrates the above processing.  FIG. 7  illustrates exemplary processing of a VoIP 9-1-1 call in an implementation consistent with the principles of the invention. In this example, assume that a user at user device  130  places a VoIP 9-1-1 call by dialing 9-1-1. In response, user device  130  may determine its current location by capturing current GPS data. If, as set forth above, user device  130  is unable to capture current GPS data, user device  130  may retrieve the recently captured GPS data from, for example, memory  230 , GPS device  260 , or from some other location. Assume that the user device  130  captures the following GPS data: 89.59.999,N,179.59.999,W. User device  130  may transmit the dialed digits (i.e., 9-1-1), the ANI of user device  130  (assumed to be “555-555-5555” for this example), and the GPS data (i.e., 89.59.999, N, 179.59.999, W) to 9-1-1 service provider  140 . 
     In response, 9-1-1 service provider  140  may use the GPS data to identify a PSAP for handling the 9-1-1 call. It is assumed for this example that 9-1-1 service provider  140  identifies PSAP  150  as the closest PSAP to the current location of user device  130 . 9-1-1 service provider  140  may obtain a pANI for PSAP  150  that will be used to route the 9-1-1 call to PSAP  150 . 9-1-1 service provider  140  may also convert the GPS data to a format that is capable of being processed by PSAP  150 . For example, if PSAP  150  is capable of processing wireless Phase I or Phase II calls, 9-1-1 service provider  140  may convert the GPS data to the format used by PSAP  150 . The formatted GPS data is referred to in  FIG. 7  as “location data.” 9-1-1 service provider  140  may forward the 9-1-1 call from user device  130  to PSAP  150 . 9-1-1 service provider  140  may also forward the location data to PSAP  150 . 
     9-1-1 service provider  140  may update ALI device  160  with the current location of user device  130 . 9-1-1 service provider  140  may, for example, forward the ANI of user device  130  (i.e., 555-555-5555) and either the GPS data (i.e., 89.59.999, N, 179.59.999, W) or the location data, which may or may not be formatted in a similar manner as the location data forwarded, to PSAP  150 . 
       FIG. 8  illustrates an exemplary process for updating ALI device  160  with current location information for a user device  130  in an implementation consistent with the principles of the invention. Processing may begin with user device  130  determining whether user device  130  is on-line (e.g., connected to network  110  or another network) (act  810 ). If user device  130  is not on-line, processing may return to act  810  with user device  130  periodically determining whether user device  130  is on-line. 
     If user device  130  is determined to be on-line, user device  130  may, at a periodic interval, capture current GPS data (act  820 ). In one implementation, user device  130  may capture current GPS data using GPS device  260 . The GPS data may be in the form of latitude and longitude coordinates or in another form. If user device  130  is unable to capture current GPS data, user device  130  may retrieve the most recently captured GPS data from, for example, memory  230 , GPS device  260 , or some other location. The interval at which the GPS data is captured may be configurable by the user of user device  130 . 
     User device  130  may transmit the GPS data (or the most recently captured GPS data) to 9-1-1 service provider  140  (act  830 ). The GPS data may be transmitted using an IP format, a real time protocol (RTP) format, or another format. User device  130  may also transmit ANI information (e.g., a phone number associated with user device  130 ) to 9-1-1 service provider  140  (act  830 ). The ANI information may be transmitted with the GPS data or separately from the GPS data. 
     9-1-1 service provider  140  may update ALI device  160  (act  840 ). In one implementation consistent with the principles of the invention, 9-1-1 service provider  140  may forward the ANI information and the GPS data to ALI device  160 . ALI device  160  may lookup the ANI information in, for example, database  510  and replace any existing location information with the GPS data received from 9-1-1 service provider  140 . If necessary, 9-1-1 service provider  140  or ALI device  160  may convert the GPS data into a desired format prior to storing the location information in database  510 . 
     In this way, 9-1-1 service provider  140  will be aware of the current location of user device  130  when the user device  130  is on-line. 9-1-1 service provider  140  may periodically update the location of user device  130  in ALI device  160  whether or not a 9-1-1 call is made from user device  130 . As a result, ALI device  160  will store accurate/recent location information for user device  130 , thus providing PSAPs with actionable dispatch information in cases where the 9-1-1 caller is unable to verbally relay his/her location information or is temporarily unable to receive a GPS signal. 
     CONCLUSION 
     Implementations consistent with the principles of the invention use GPS coordinates from a user device for routing a 9-1-1 call from the user device to the appropriate PSAP. In one implementation, the GPS coordinates are provided from a GPS device that is associated with the user device. Implementations consistent with the principles of the invention also allow for periodic updates of ALI information for user devices. 
     The foregoing description of exemplary implementations of the invention provides illustration and description, but is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. For example, while the above description focused on user device  130 , 9-1-1 service provider  140 , and PSAP  150  performing certain acts, it will be appreciated that in other implementations consistent with the principles of the invention, the acts described above may be performed by another device in system  100 . 
     Moreover, it will be appreciated that the techniques described herein are equally applicable to non-9-1-1 scenarios. For example, one or more of the techniques described above may be used for VoIP usage tracking and call statistics monitoring/analysis, personalized location-based services (e.g., retail location finder, local new/weather, etc.), and/or geographic information systems (GIS) based enterprise services (e.g., field services, dispatch operations, etc.). 
     While series of acts have been described with respect to  FIGS. 6 and 8 , the order of the acts may be varied in other implementations consistent with the invention. Moreover, non-dependent acts may be implemented in parallel. 
     It will be apparent to one of ordinary skill in the art that aspects of the invention, as described above, may be implemented in many different forms of software, firmware, and hardware in the implementations illustrated in the figures. The actual software code or specialized control hardware used to implement aspects consistent with the principles of the invention is not limiting of the invention. Thus, the operation and behavior of the aspects of the invention were described without reference to the specific software code—it being understood that one of ordinary skill in the art would be able to design software and control hardware to implement the aspects based on the description herein. 
     Further, certain portions of the invention may be implemented as “logic” that performs one or more functions. This logic may include hardware, such as an application specific integrated circuit or a field programmable gate array, software, or a combination of hardware and software. 
     No element, act, or instruction used in the description of the present application should be construed as critical or essential to the invention unless explicitly described as such. Also, as used herein, the article “a” is intended to include one or more items. Where only one item is intended, the term “one” or similar language is used. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.