CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application entitled, â€œMethod and System for Obtaining Emergency Caller Locationâ€ , Ser. No. 12/205,883, filed on Sep. 7, 2008. Patent application Ser. No. 12/205,883 is in turn a continuation of U.S. patent application with Ser. No. 11/750,281, filed on May 17, 2007, which issued as U.S. Pat. No. 8,032,109 on Oct. 4, 2011. Patent application Ser. No. 11/750,281 is in turn a continuation of U.S. patent application with Ser. No. 11/182,219, filed on Jul. 14, 2005, and which issued as U.S. Pat. No. 7,272,402 on Sep. 18, 2007.

BACKGROUND OF THE INVENTION

1. Field

This invention relates generally to telecommunications, more specifically, to a method and system to provide location information for voice calls.

2. Related Art

Around the world there are many emergency telephone numbers. For example, in the United States of America, the three-digit telephone number â€œ911â€ is designated as the universal emergency telephone number. In the case of an emergency, a person can call 911 to reach an operator who can dispatch appropriate emergency services. To help provide the timeliest response, it is helpful and often necessary to have the location of the caller reported to the emergency service dispatcher. This is feature is of utmost importance when the caller is a young child, someone who is very ill or injured or otherwise unable to effectively communicate their location to the emergency services dispatcher. For these services to function properly, the telephone service provider must have means of identifying and reporting the location of the emergency caller.

In a typical scenario, when a subscriber subscribes to a residential telephone service from a service provider, the service provider assigns a telephone number for that subscription and allocates an access line to the subscriber's residence for the service. The access line connects to a telephone system of the residential telephone service. A user connects a telephone to the access line and uses the telephone to receive the residential telephone service.

The location of the subscription is the connecting point of the access line and the telephone. The location is typically the street address of the subscriber's residence. The service provider submits the telephone number and the location of the subscription to create a record in an Automatic Location identity (ALI) database. The record maps the telephone number to the location of the subscription. One of the usages of ALI database is for Emergency call purpose.

When a caller uses the telephone to make an emergency call by dialing â€œ911â€ , the telephone system determines the telephone number associated with the subscription. The telephone system sends a call request to a 911 selective router telephone system. The call request includes the telephone number.

The 911-selective router telephone system receives the telephone number in the call request and retrieves from the ALI database the location of the subscription based on the telephone number. The location is presumably where the caller of the emergency call is. The 911-selective router telephone system uses the location to select a Public Safety Answering Point (PSAP), which is a telephone system. The 911-selective router telephone system further sends the emergency call request to the PSAP. The call request also includes the telephone number.

The PSAP presents the emergency call to an emergency call agent. The PSAP also retrieves from the ALI database the location of the subscription based on the telephone number in the emergency call request, and informs the emergency call agent of the location from which the call originated. The agent uses the location to dispatch emergency personnel and services.

Recently, various service providers have been rolling out new telephone services. These telephone services include cellular telephone services, and Voice over IP (VoIP) telephone services. Although these telephone services are not the same as traditional residential telephone services, they are either marketed as residential telephone services or subscribers use them as if they are equivalent to residential telephone services. Many consumers mistakenly assume that 911 or emergency services will be available in these new telephone services as they are in traditional residential telephone services. However this is often not the case. Cellular and VoIP telephone services, due to their ability to move from one physical location to another, present a fairly complex problem when it come to providing emergency call services. Especially when those services are highly dependent on knowing from whence the emergency call is being made.

In the case of VoIP telephone service, a user receives VoIP telephone service by connecting an IP telephone to a VoIP telephone system via the Internet. In one scenario, the IP telephone may be connected to a home DSL broadband Internet access gateway. It is also possible to connect the same IP telephone to a neighbor's Cable Modem broadband Internet access gateway. As a further convenience, is it also possible to connect an IP telephone to the IP network of a hotel during an out-of-town trip. In each example, the IP telephone is used to receive VoIP telephone service. While the convenience of being able to travel to any location with an appropriate Internet access, there is a danger associated with assuming that emergency services will be available on the IP telephone as on a regular telephone. To illustrate this danger, consider the following scenario.

While out of town, a user has an accident or encounters an emergency. The user calls 911 on an IP telephone that they have brought from home. The user assumes the 911-emergency call center would know her location, and expects emergency services to arrive in a short period of time. When the emergency call is not answered or when emergency services do not arrive in an hour, the user panics. Whilst in the hotel, the user's spouse calls the user's IP telephone number from their home concerned that emergency services were dispatched to their home for her whilst she is away. From the IP telephone service, the emergency dispatch services had no way of knowing her location.

As shown in the new telephone services, there is a need for a fundamentally new solution to provide the correct location of a caller during an emergency call.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present include systems and methods for obtaining the location of a caller during a telephone call.

In one embodiment, a phone system obtains the subscriber access line identity of a subscriber access line and sends it to a subscriber location query system which then returns a subscriber location or a subscriber location record.

In another embodiment, subscriber phone equipment or phone can store a subscriber access line identity. The subscriber line identity stored in the subscriber phone equipment or phone can be used to retrieve the subscriber location record with the corresponding subscriber access line identity stored its subscriber access line identity attribute and a known location stored in its subscriber location attribute to compare to subscriber access line identities obtained during calls to determine if the subscriber phone equipment has changed location.

In yet another embodiment, the emergency call capabilities of a subscriber access line are determined by an emergency call test module sending out a test signal or query to a subscriber access line module, a phone system or subscriber access line.

Additional embodiments will be evident from the following detailed description and accompanying drawings, which provide a better understanding of the nature and advantages of the present invention

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE FIGURES

FIG. 1 is a block diagram illustrating the connections between subscriber access line module and subscriber phone equipment through a subscriber access line.

FIG. 2 is a block diagram illustrating a subscriber location record.

FIG. 3 is a block diagram illustrating the connections between a subscriber location datastore and a subscriber location query system.

FIG. 4 is a block diagram illustrating a system for obtaining a subscriber location during a call.

FIG. 5 is a block diagram illustrating a system for handling an emergency call.

FIG. 6 is a block diagram illustrating a method of testing whether or not an emergency call can be made using a subscriber access line.

FIG. 7 is a block diagram illustrating a system for determining whether or not subscriber phone equipment has changed location.

DETAILED DESCRIPTION OF THE INVENTION

Subscriber Phone Equipment, Subscriber Access Line, and Subscriber Access Line Module

FIG. 1 illustrates a subscriber access line module 130 connection to subscriber phone equipment 110. Subscriber phone equipment 110 connects to subscriber access line module 130 via a subscriber access line 135. Subscriber access line module 130 can connect to multiple subscriber phone equipment simultaneously through multiple subscriber access lines. Each subscriber access line 135 has a subscriber access line identity. Each subscriber access line 135 has a subscriber location. The subscriber location of a subscriber access line 135 is the location where the subscriber access line 135 connects to subscriber phone equipment 110. In one embodiment, a subscriber location includes a street address. In another embodiment, a subscriber location includes a building number. In yet another embodiment, a subscriber location includes a room number. In one embodiment, a subscriber location includes a cubicle number. In a different embodiment, a subscriber location includes a geophysical location.

Subscriber access line module 130 manages the association between a subscriber access line 135 and the subscriber access line identity that identifies the subscriber access line 135. In one embodiment, subscriber access line module 130 includes a Master Distribution Frame (MDF). In another embodiment, subscriber access line module 130 includes a Digital Access Line Access Module (DSLAM). In yet another embodiment, subscriber access line module 130 includes a Digital Loop Carrier (DLC). In a different embodiment, subscriber access line module 130 includes Cable Headend equipment, such as a Cable Modem Termination System (CMTS) or a Cable Data Modem Termination System (CDMTS). In another embodiment, subscriber access line module 130 includes radio network access equipment, such as base stations and base station controllers (BSC).

In one embodiment, subscriber access line 135 includes a copper local loop. In another embodiment, subscriber access line 135 includes a coaxial cable. In another embodiment, subscriber access line 135 includes a radio frequency band. In one embodiment, subscriber access line 135 includes a multiplex channel within the radio frequency band. In another embodiment, the multiplex channel is based on Time Division Multiplexing Access (TDMA) technology. In another embodiment, the multiplex channel is based on Code Division Multiplexing Access (CDMA) technology. In yet another embodiment, the multiplex channel is based on Frequency Division Multiplexing Access (FDMA) technology.

Subscriber Location Record and Subscriber Location Datastore

FIG. 2 illustrates a subscriber location record. A subscriber location record 280 comprises a subscriber access line identity attribute 285 and a subscriber location attribute 287. In one embodiment, subscriber access line identity attribute 285 includes the subscriber access line identity of a subscriber access line. In one embodiment, subscriber location attribute 287 includes the subscriber location of the subscriber access line. The location stored in the subscriber location attribute can be a physical address such as a street address, a building number, a cubicle number, or geophysical location coordinates.

Subscriber Location Datastore and Subscriber Location Query System

FIG. 3 illustrates a process for querying a subscriber location. Subscriber location datastore 370 connects to a subscriber location query system 380. Subscriber location datastore 370 includes a plurality of subscriber location records. Subscriber location query system 380 receives a query for a subscriber location. The query includes a subscriber access line identity 312. In one embodiment, subscriber location query system 380 compares the subscriber access line identity with the subscriber access line identity attribute of multiple subscriber location records in subscriber location datastore 370. If a matching subscriber location record exists, subscriber location query system 380 selects one or more of the matching subscriber location record 316.

Subscriber location query system 380 sends the result 318 in response to the query. In one embodiment, the result 318 is the subscriber location extracted from the subscriber location attribute of the selected subscriber location record 316. In another embodiment, the result is one or more of the selected subscriber location record 316.

In one embodiment, subscriber location query system 380 receives the query from a network. In one embodiment, the network is a Signaling System 7 (SS7) network. In another embodiment, the network is an Internet Protocol (IP) network. In yet another embodiment, subscriber location query system 380 receives the query over a circuitry connection. In a different embodiment, subscriber location query system 380 receives the query over an Application Programming Interface (API). In a one embodiment, subscriber location query system 380 receives the query via a standard base database access protocol. In another embodiment, subscriber location query system 380 receives the query via a proprietary protocol.

A Method of Obtaining Subscriber Location During a Call

FIG. 4 illustrates a system for obtaining a subscriber location during a call.

Subscriber phone equipment 410 connects to a subscriber access line module 430 over a subscriber access line 435. A phone 417 connects to subscriber access line module 430 over the subscriber access line 435. Subscriber access line module 430 connects to a phone system 490. A user uses phone 417 to make a call.

Phone system 490 receives and processes the call from phone 417. Phone system 490 determines the subscriber access line identity of the subscriber access line as to where phone 417 is connected.

In one embodiment, phone system 490 determines the subscriber access line identity by correlating the resources in phone system 490. In one embodiment, the resources include a line card and a port. In another embodiment, the resources include a multiplexing channel in the communications media between phone system 490 and subscriber access line module 430.

In another embodiment, phone system 490 determines the subscriber access line identity by querying subscriber access line module 430. In one embodiment, phone system 490 queries subscriber access line module 430 during processing of the call. In another embodiment, phone system 490 queries subscriber access line module 430 before the call.

In another embodiment, phone system 490 connects to subscriber phone equipment 410. Subscriber phone equipment 410 obtains the subscriber access line identity of subscriber access line 435 from subscriber access line module 430. Phone system 490 determines the subscriber access line identity by querying subscriber phone equipment 410. In one embodiment, phone system 490 queries subscriber phone equipment 410 during processing of the call. In another embodiment, phone system 490 queries subscriber phone equipment 410 before the call.

In yet another embodiment, phone 417 stores, includes or otherwise has the subscriber access line identity of subscriber access line 435. Phone system 490 determines the subscriber access line identity from phone 417. In one embodiment, phone system 490 determines the subscriber access line identity from phone 417 during processing of the call. In another embodiment, phone system 490 determines the subscriber access line identity from phone 417 before the call.

In FIG. 4, phone system 490 connects to a subscriber location query system 480. Phone system 490 sends a query to subscriber location query system 480. The query includes the determined subscriber access line identity. Phone system 490 receives a subscriber location from subscriber location query system 480.

In one embodiment, phone system 490 connects to another phone system 495. Phone system 490 sends a call request to phone system 495. In one embodiment, phone system 490 includes the determined subscriber access line identity in the call request. phone system 495 receives the determined subscriber access line identity from phone system 490. Phone system 495 determines the subscriber location from the received subscriber access line identity by querying subscriber location query system 480.

A Method of Obtaining the Location of a Caller During an Emergency Call.

FIG. 5 illustrates a method of handling an emergency call. Phone system 590 connects to an emergency response phone system 595. Emergency response phone system 595 comprises one or more phone systems. Emergency response phone system 595 connects to subscriber location query system 580. Subscriber phone equipment 510 connects to a subscriber access line module 530 over a subscriber access line 535. phone 517 connects to subscriber access line module 530 over the subscriber access line 535. Subscriber access line module 530 connects to phone system 590.

A user makes an emergency call by dialing an emergency number at phone 517. In one embodiment, the emergency number is â€œEmergencyâ€ . In another embodiment, the emergency number is â€œ999â€ . In yet another embodiment, the emergency number is â€œ911â€ . Phone system 590 receives the emergency call, and determines the subscriber access line identity of subscriber access line 535 as illustrated in FIG. 4.

Phone system 590 routes the emergency call to emergency response phone system 595 and sends the determined subscriber access line identity to emergency response phone system 595.

Emergency response phone system 595 receives the emergency call and the subscriber access line identity. Emergency response phone system 595 determines the subscriber location by querying the subscriber location query system 580 using the received subscriber access line identity. Emergency response phone system 595 presents the emergency call, including the subscriber location, to an agent. The agent dispatches emergency personnel to subscriber location. In one embodiment, the agent dispatches emergency personnel to the street address indicated in the subscriber location. In an embodiment, the agent dispatches emergency personnel to the cubical of a building indicated in the subscriber location. In a different embodiment, the agent dispatches emergency personnel to search in the geophysical location indicated in the subscriber location.

A Method of Obtaining if an Emergency Call can be Made Using a Subscriber Access Line

FIG. 6 illustrates a method of obtaining if an emergency call can be made using a subscriber access line. Subscriber phone equipment 610 includes an emergency call test module 615. Subscriber phone equipment 610 connects to subscriber access line module 630 over subscriber access line 635. Subscriber access line module 630 connects to a phone system 690. Emergency call test module 615 performs a test to determine if an emergency call can be made using the subscriber access line 635.

In one embodiment, emergency call test module 615 queries subscriber access line module 630. Subscriber access line module 630 responds with an indication whether or not an emergency call can be made. Emergency call test module 615 checks the indication. If the indication is positive, emergency call test module 615 determines that an emergency call can be made using the subscriber access line 635.

In another embodiment, subscriber phone equipment 630 connects to phone system 690. Emergency call test module 615 queries phone system 690. Phone system 690 responds with an indication whether or not an emergency call can be made. Emergency call test module 615 checks the indication. If the indication is positive, emergency call test module 615 determines that an emergency call can be made using the subscriber access line 635.

In one embodiment, emergency call test module 615 sends an off hook signal towards subscriber access line 635, and checks for an indication of a dial tone. If the indication is positive, emergency call test module 615 determines that an emergency call can be made using the subscriber access line 635.

In one embodiment, emergency call test module 615 repeats the process a multiple times before determining if an emergency call can be made using the subscriber access line 635.

In one embodiment, subscriber phone equipment 610 connects to a telephone. Subscriber phone equipment 610 informs the telephone if an emergency call can be made using the subscriber access line 635.

In one embodiment, subscriber phone equipment 610 further includes an emergency call test indicator 613. Emergency call test module 615 connects to an emergency call test indicator 613. In one embodiment, emergency call test indicator 613 includes a visual indicator such as a light or display.

In one embodiment, emergency call test indicator 613 includes a LED as the visual indicator. If emergency call test module 615 determines that an emergency call can be made using the subscriber access line 635, emergency call test module 615 turns the LED or other visual indicator to green. In one embodiment, if emergency call test module 615 cannot determine an emergency call can be made using the subscriber access line 635, emergency call test module 615 turns the LED to red.

In another embodiment, emergency call test indicator 613 includes a text display panel. If emergency call test module 615 determines an emergency call can be made using the subscriber access line 635, emergency call test module 615 displays â€œemergency call Test Succeedsâ€ on the display panel. In one embodiment, emergency call test module 615 cannot determine that an emergency call can be made using the subscriber access line 635 emergency call test module 615 displays â€œemergency call Test failsâ€ on the display panel.

In one embodiment, emergency call test module 615 determines repeatedly if an emergency call can be made using the subscriber access line 635. In one embodiment, emergency call test module 615 performs the process every 30 minutes. In another embodiment, emergency call test module 615 performs the process every hour. In yet another embodiment, emergency call test module 615 performs the process when subscriber phone equipment 610 powers up. In a different embodiment, emergency call test module 615 performs the process when a telephone call is made.

A Method of Determining Whether or not Subscriber Phone Equipment has Changed Location

FIG. 7 illustrates a process to determine whether or not subscriber phone equipment has changed location. Subscriber phone equipment 710 includes a location test module 715.

A Method of Determining Whether or not Subscriber Phone Equipment has Changed Location Based on Subscriber Access Line Identity

In one embodiment, location test module 715 determines whether or not subscriber phone equipment 710 has changed location by examining the subscriber access line identity of subscriber access line 735. Subscriber phone equipment 710 connects to subscriber access line module 730 over subscriber access line 735. Subscriber access line module 730 connects to a phone system 790.

In one embodiment, location test module 715 connects to datastore 719. Datastore 719 stores a stored subscriber access line identity 718. The stored subscriber access line identity 718 is a subscriber access line identity identifying a subscriber access line with subscriber location being the correct location of the subscriber phone equipment 710. In one embodiment, datastore 719 is a flash memory. In another embodiment, datastore is a hard disk. In yet another embodiment, datastore 719 is a memory.

Location test module 715 obtains the stored subscriber access line identity 718 and stores the stored subscriber access line identity 718 in datastore 719. In one embodiment, the stored subscriber access line identity 718 is determined when the service provider establishes a service for the subscriber. In one embodiment, during service establishment, the service provider informs the location test module 715 of the stored subscriber access line identity 718. In another embodiment, location test module 715 obtains from subscriber access line module 730 the stored subscriber access line identity 718. In another embodiment, stored subscriber access line identity 718 is determined during a service change. In another scenario, the subscriber moves subscriber phone equipment 710 to a new location, and submits a new address to the service provider. The service provider determines a new stored subscriber access line identity 718. In another embodiment, the service provider informs the location test module 715 of the new stored subscriber access line identity 718. In yet another embodiment, location test module 715 obtains from subscriber access line module 730 the new stored subscriber access line identity 718.

In one embodiment, location test module 715 connects to a phone system 790. Location test module 715 obtains the stored subscriber line identity 718 from phone system 790.

In one embodiment, location test module 715 connects to a phone 717. Location test module 715 obtains stored subscriber access line identity 718 from phone 717.

In one embodiment, location test module 715 is informed when a new stored subscriber line identity 718 is available. In another embodiment, location test module 715 checks for a new stored subscriber line identity 718. In an embodiment, location test module 715 checks every 5 minutes. In a different embodiment, location test module 715 checks every hour.

Location test module 715 determines whether or not subscriber phone equipment 710 has changed location by matching the stored subscriber access line identity 718 against the subscriber access line identity of subscriber access line 735. If the match succeeds, location test module 715 concludes that subscriber phone equipment 710 has not changed location.

In one embodiment, location test module 715 obtains the subscriber access line identity of subscriber access line 735 from subscriber access line module 730. In another embodiment, location test module 715 obtains the subscriber access line identity of subscriber access line 735 from phone system 790. In yet a different embodiment, location test module 715 obtains the subscriber access line identity of subscriber access line 735 from phone 717.

A Method of Determining Whether or not Subscriber Phone Equipment has Changed Location in Voice Over IP (VoIP) Phone Services

In one embodiment, phone 717 connects to phone system 790 based on VoIP service. Phone 717 has an IP address. Phone 717 has an IP address as seen by phone system 790.

In one embodiment, location test module 715 sends a message to phone 717. In one embodiment, phone 717 responds with an indication about whether or not the IP address of phone 717 has changed. In another embodiment, phone 717 responds with an indication about whether or not the IP address of phone 717 as seen by phone system 790 has changed. Location test module 715 can determine based on the indication received from phone 717 whether or not subscriber phone equipment 710 has changed location.

In one embodiment, location test module 715 sends a message to phone system 790. In one embodiment, phone system 790 responds with an indication about whether or not the IP address of phone 717 has changed. In another embodiment, phone system 790 responds with an indication about whether or not the IP address of phone 717 as seen by phone system 790 has changed. Location test module 715 can determine based on the indication received from phone 717 whether or not subscriber phone equipment 710 has changed location.

In one embodiment, location test module 715 sends a message to phone 717 and a message to phone system 790. Location test module 715 concludes that subscriber phone equipment 710 has not changed location if phone 717 responds that the IP address of phone 717 has not changed and phone system 790 responds that the IP address of phone 717 as seen by phone system 790 has not changed.

In another embodiment, location test module 715 tests whether or not subscriber phone equipment 710 has changed location every 30 minutes. In another embodiment, location test module 715 tests whether or not subscriber phone equipment 710 has changed location every hour. In yet another embodiment, location test module 715 tests whether or not subscriber phone equipment 710 has changed location when subscriber phone equipment 710 powers up. In a different embodiment, location test module 715 tests whether or not subscriber phone equipment 710 has changed location when a user makes a telephone call.

In one embodiment, subscriber phone equipment 710 connects to phone 717. Subscriber phone equipment 710 informs phone 717 whether or not subscriber phone equipment 710 has changed location. In one embodiment, subscriber phone equipment 710 further includes a location test indicator 713. Location test module 715 connects to the location test indicator 713.

In according to one embodiment, location test indicator 713 includes a visual indicator such as a light or a display. In one embodiment, the visual indicator is an LED. If location test module 715 determines that subscriber phone equipment 710 has not changed location, location test module 715 turns the LED to green. In one embodiment, if location test module 715 cannot determine that subscriber phone equipment 710 has not changed location, location test module 715 turns the LED to red. In another embodiment, the visual indicator is a display panel. If location test module 715 determines that subscriber phone equipment 710 has not changed location, location test module 717 displays â€œLocation correctâ€ on the display panel. If location test module 715 cannot determine that subscriber phone equipment 710 has not changed location, location Test module 717 displays â€œLocation may be incorrectâ€ on the display panel.

Combining Emergency Call Test and Location Test

In one embodiment, subscriber phone equipment includes an emergency call test module and a location test module. Subscriber phone equipment can perform both tests provided for by the emergency call test module and the location test module. In one embodiment, subscriber phone equipment further connects to a test indicator. The test indicator can include a visual indicator such as a light or a display.

In one embodiment, emergency call test module determines whether or not an emergency call can be made and location test module determines whether or not subscriber phone equipment has changed location. In one embodiment, emergency call test module determines that an emergency call can be made and determines that subscriber phone equipment has not changed locations; then subscriber phone equipment turns the visual indicator, such as an LED, to green. In another embodiment, emergency call test module determines that an emergency call can be made and location test module cannot determine whether or not subscriber phone equipment has changed location; then subscriber phone equipment turns the visual indicator, such as an LED, to yellow. In yet another embodiment, emergency call test module cannot determine that an emergency call can be made and location test module determines that subscriber phone equipment has not changed location; subscriber phone equipment turns the LED to amber. In one other embodiment, emergency call test module cannot determine that an emergency call can be made and location test module cannot determine that subscriber phone equipment has not changed location; subscriber phone equipment turns the LED to red.

In a different embodiment, the test indicator visual indicator is a display panel. Subscriber phone equipment displays corresponding messages on the display panel based on the combined test results of emergency call test module and location test module.

Subscriber Location Changes During an Emergency Call

While a user is making an emergency call, the user may move from a location to another location. The phone system handling the call can discover, from time to time, the subscriber access line identity of the subscriber access line to which the phone is connected. In one embodiment, after obtaining a subscriber access line identity, the phone system sends the subscriber access line identity to the emergency response phone system. In another embodiment, the phone system detects a change in subscriber access line identity, and sends the new subscriber access line identity to the emergency response phone system. The emergency response phone system further presents to the agent with an updated subscriber location.

A Method of Selecting a Phone System while Making Emergency Calls in a VoIP Service Scenario

In FIG. 5, when a phone 517 makes an emergency call, phone 517 routes the emergency call to a phone system 590. In one embodiment, the telephone service is a VoIP service. The VoIP service provider is typically not the service provider for the subscriber access line 535. In one embodiment, the subscriber access line service provider offers telephone services and has a plurality of phone system from the subscriber access line service provider. When a user makes an emergency call, the user can select a phone system from the subscriber access line service provider to handle the emergency call.

In one embodiment, the phone 517 recognizes the emergency call and routes the emergency call to a phone system from the subscriber access line service provider. In another embodiment, the phone 517 is connected to the subscriber phone equipment 510. The subscriber phone equipment 510 recognizes the emergency call and routes the emergency call to a phone system from the subscriber access line service provider.

In another embodiment, the subscriber access line module 530 recognizes the emergency call and routes the emergency call to a phone system from the subscriber access line service provider.

Types of Phone Calls that Require Subscriber Location Information

The above description applies to emergency calls that require subscriber location information. However, there are many other scenarios in which would be helpful, advantageous or necessary to obtain the subscriber location of a telephone call. In one embodiment, phone system can use subscriber access line identities to determine the location information for calls such as location specific directory services, marketing information for premium pay per use phone services and toll-free service calls.

Described herein are techniques for methods and systems of obtaining the location of a caller during an emergency phone call. In the following description, for purposes of explanation, numerous examples and specific details are set forth in order to provide a thorough understanding of the present invention. It will be evident, however, to one skilled in the art that the present invention as defined by the claims may include some or all of the features in these examples alone or in combination with other features described below, and may further include obvious modifications and equivalents of the features and concepts described herein.