Abstract:
A telephony service device has a digital interface, an analog telephone line interface, and circuitry operable to provide telephone service over the analog telephone line interface via a network connection to the digital interface. A telephone network signal detector comprising a part of the device is operable to detect a telephone network signal on one or more telephone lines connected to the analog telephone interface, and a switch is operable to automatically connect the telephony service device to a line on the analog telephone interface on which the telephone network signal detector did not detect a telephone network signal.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates generally to telephone systems, and more specifically to autosensing a public switched telephone network-type system.  
         BACKGROUND OF THE INVENTION  
         [0002]    The traditional international telephone system, commonly known as the Public Switched Telephone Network (PSTN), comprises analog voice signals carried over switched copper wires to provide telephony service to subscribers. The telephone service provided via the PSTN is commonly known as POTS, or Plain Old Telephone Service. As the system matured, various technologies such as radio and fiber optic communication were used to improve the capacity or reliability of certain stages of the system, such as to carry long distance traffic between areas of the country and world. But, the local exchange carriers still provide a traditional PSTN copper connection to consumers, so that older traditional telephones are still compatible with the PSTN system.  
           [0003]    New telecommunications equipment such as fax machines and modems are specifically designed to be compatible with the PSTN telephone network, and still connect to the telephone system via the same RJ-11 type connectors that standard telephones have traditionally used. Because even residential homes often desire multiple lines of PSTN service, the standard RJ-11 connectors and related house wiring are typically installed configured with two or more pair of wires to support a corresponding two or more lines of POTS service.  
           [0004]    More recently, PSTN lines have been used in some systems to provide Digital Subscriber Line (DSL) service, which comprises a high-bandwidth digital connection between a switching device and the subscriber&#39;s premises equipment. DSL is used to provide a variety of services, including Internet service and telephony service. Internet service is provided via a DSL modem that interfaces the DSL signal coming in through the PSTN system to a computer or computer network, and telephony service is provided via a device such as an IAD, or integrated access device.  
           [0005]    In voice telephony over DSL, the IAD or other device must interface with a telephone system within the subscriber&#39;s location to provide connection to traditional telephone equipment via the traditional RJ11 telephone jacks and copper wiring. Therefore, the installer of such a system must determine what pair of wires the DSL signal is carried on, connect the DSL connection of the IAD or other device to the DSL signal pair, and connect the subscriber&#39;s telephony equipment and IAD device telephony connection to another pair. This must be done to prevent the locally generated telephony signals from interfering with the signal provided by the local telephone service provider, and generally requires a telephone service technician to visit the premises to properly configure the system. Easy and efficient installation of such a system is therefore desirable. 
       
    
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0006]    [0006]FIG. 1 illustrates an example topology of a system consistent with an embodiment of the present invention.  
         [0007]    [0007]FIG. 2 illustrates the configuration of an RJ-11 connector, as may be used with various embodiments of the present invention.  
         [0008]    [0008]FIG. 3 illustrates a flowchart of a method of practicing an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0009]    In the following detailed description of sample embodiments of the invention, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific sample embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical, electrical, and other changes may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the invention is defined only by the appended claims.  
         [0010]    The present invention provides in various embodiments a system and method for automatically connecting a device to a telephone line on which telephone network signals are not present. Circuitry detects a telephone network signal on one or more of a plurality of telephone lines, and connects a device to a line on which a network signal was not detected. Such a system enables easy installation and configuration of a telephony system such as a Voice over DSL (VoDSL) or other such system that provides analog telephone service from within a building.  
         [0011]    [0011]FIG. 1 illustrates an example topology of a system consistent with an embodiment of the present invention. A service provider  101  provides a copper wire pair connection  102  to the subscriber, which carries both POTS analog telephone and DSL digital data services. The telephone line connection  102  enters the customer premises at  103 , and is routed via a cable that contains a second pair of wires for a second telephone line connection  104 .  
         [0012]    A Voice over DSL (VoDSL) Integrated Access Device (IAD)  105  is connected to the telephone line connections  102  and  104  via an RJ11 connection  106 , and in some embodiments is further connected to the telephone lines  102  and  104  via a second RJ11 connection  107 . Telephone  108  is connected to telephone line connections  102  and  104  via RJ11 connection  109 , and telephone  110  is similarly connected to telephone line connections  102  and  104  via RJ11 connection  111 .  
         [0013]    In operation, the VoDSL LAD  105  is first installed in a manner that comprises connecting the IAD to the incoming copper wire pair  102  over which the service provider  101  provides the DSL signal. The IAD is also connected to copper wire pair  104 , via RJ11 connection  106  or  107 .  
         [0014]    The VoDSL IAD detects which of the connected telephone lines  102  and  104  have a PSTN signal present, and after detecting that line  102  has a signal present from service provider  102  establishes an analog telephone service signal on  104 . Detecting the PSTN signal in various embodiments comprises detecting a voltage between the pair of copper wires that form each telephone line, or detecting another signal associated with an active telephone service line.  
         [0015]    Telephone  108  is plugged in to RJ11 connection  109 , and telephone  18  is configured to connect to the first telephone line  102 . Telephone  110  is plugged into RJ11 connection  111 , and the telephone  110  is configured to connect to line  104 . Because telephone  108  is connected to the telephone line  102 , its telephone service is provided by the service provider  101 . Telephone  110  is connected to telephone line  104 , which is not connected to the service provider  101  but is connected to the VoDSL LAD  105 . Telephone service for telephone  110  is therefore not provided by service provider  108  directly, but is provided via VoDSL IAD  105  which provides analog telephone service by transmitting and receiving voice data as digital data over its DSL connection.  
         [0016]    [0016]FIG. 2 illustrates the configuration of a typical RJ-11 connector, as may be used with various embodiments of the present invention. The telephone line designated as line one comprises a pair of wires connected to connections  201 , line two comprises a pair of wires connected to connectors  202 , and line three comprises a pair of wires connected to connectors  203 . In this particular embodiment, a faceplate  204  has a recess or socket  205  which houses the connectors  201 - 203 . The recess or socket  205  receives a matching plug that mates with connectors  201 - 203 , and provides connection to telephone equipment.  
         [0017]    A telephone or other device such as the VoDSL IAD  105  of FIG. 1 can connect to one, two, or three telephone lines via the line connection pairs  201 - 203  of FIG. 2, all through a single RJ11 connector. Telephones that operate on a single line may be configured or rewired to connect to any of these three lines, or multiple line telephones may be used to provide access to lines other than line one. In this manner, either of phones  108  or  110  may be configured or selected to operate with either telephone line  102  or  104 .  
         [0018]    The configurations shown here illustrate how configuration of a phone system, either operating alone or in conjunction with one or more other lines of telephone service, can uses an unused line of telephone service within a building to provide telephone service via a VoDSL IAD or other such device. Automatic detection of telephone service on connected lines enables automatic selection of a connected telephone line that is not already being used for providing telephone service via the IAD device.  
         [0019]    In further embodiments of the invention, the IAD device  105  is not a DSL modem or device but is instead a cable modem connected to a network via a television cable or is another telephony device. In still further embodiments, device  105  is not a voice-over-data modem or other telephony service device, but is any other type of device which can make use of unused telephone lines of service within a building or house. Examples include home automation systems, alarm systems, thermostat or other HVAC control systems, networking systems, and other such systems.  
         [0020]    The device will in some embodiments provide notification to a user of the resulting configuration, such as by use of indicator lights on the device that light to indicate which lines are already being used and to which line the device has automatically connected. In other embodiments, such notification may be provided via a network connection to an attached computer, via a device control panel display such as a LCD panel, or via any other such suitable display mechanism.  
         [0021]    [0021]FIG. 3 illustrates a flowchart of a method of practicing an embodiment of the present invention. At  301 , a device is connected to two or more telephone lines. The device in some embodiments of the invention comprises a telephone service device, such as a Voice over DSL or Voice over IP device, a DSL or cable modem, or other such device. At  302 , the device automatically detects the presence of a telephone network signal on one or more of the connected telephone lines. The network signal is in various embodiments of the invention a voltage indicating live telephone service or any other signal suitable to identify an active telephone line. At  303 , the device automatically couples itself to a telephone line other than the one or more connected lines on which a telephone network signal was detected. At  304 , the device connects with one or more other devices over the connected telephone line. In some embodiments of the invention, the one or more other devices comprise telephones, to which the first device provides telephone service.  
         [0022]    Although specific embodiments of systems and methods incorporating detection of a telephone network signal on a line and connecting a device to an unused line have been discussed in detail herein, they are only examples of the invention that illustrate such systems may be employed consistent with the appended claims. Other embodiments of the invention will utilize various combinations and configurations of the elements of the claims, all of which are within the scope of the present invention.  
         [0023]    Specific embodiments have been illustrated and described herein, but it will be appreciated by those of ordinary skill in the art that any arrangement which is calculated to achieve the same purpose may be substituted for the specific embodiments shown. This application is intended to cover any adaptations or variations of the invention. It is intended that this invention be limited only by the claims, and the full scope of equivalents thereof.