Abstract:
A system and method for polling communication lines in a communication system having a plurality of communication lines and at least one telemetry device coupled to one of the plurality of communication lines. The method comprises the steps of creating a polling signal at the network switch, transmitting the polling signal from the network switch to one of the communication lines and determining whether the one communication line is associated with the telemetry device.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to communication systems and, more particularly, to telecommunication systems which provide telemetry services. Telecommunication systems employing telemetry applications are well known. Telemetry generally involves the transmission of data which represents status information concerning a remote device or function. 
     In order to perform telemetry applications, providers of telemetry services (such as a telephone company or third party service provider) are required to communicate with one or more telemetry devices such as telemetry interface units (TIUs), meter interface units (MIUs) or directly to the telemetry units without going through an interface or gateway. 
     Utility service providers, such as local electric power, natural gas, water providers, and information service providers are capable of accessing their telemetry units (such as usage meters or display devices) located at customer locations through the telecommunication lines for the customers via a suppressed ringing protocol, such as described in U.S. Pat. No. 5,189,694 issued Feb. 23, 1993 to Garland for “Telemetry Access Arrangement” and U.S. Pat. No. 5,509,054 issued Apr. 16, 1996 to Garland for “Communication Switching System.” Both of these patents are hereby incorporated by reference with respect to such suppressed ringing and should also be referred to for general background on telephonic networks. 
     Suppressed ringing sets up a call path between a server and a telemetry device such as a TIU, MIU or a consumer premise equipment (CPE) via a public switched telephone network. The server first selectively sends a tone that alerts (wakes up) the telemetry device making it active (some go off hook to transmit data, others remain on hook to transmit data) without ringing the line connected to the telemetry device. The call path is not affected by the features on the line like call forwarding. Alternatively, a frequency shift keying (FSK) signal or a dual tone multiple frequency (DTMF) alert technique may be employed. Once the telemetry device is active, the server then communicates with the telemetry device. This allows for two way communication between the server and the telemetry device without sending a ring alert signal and distrubing (ringing) the consumers at-the location of the telemetry device or being effected by the features that the consumers may have enabled such as call forwarding, call blocking, automatic recall or other similar features. 
     Disadvantageously, in known systems, problems occur for telemetry service providers when telephone number changes are made by the end customers. Providers of telemetry services are not able to efficiently communicate with a telemetry device at a fixed location when telephone numbers are changed by a customer. Unfortunately, in this situation telemetry service providers cannot communicate with a telemetry interface (or gateway) due to the changing of directory number (DN) information associated with the premise and/or serving switch. The task of associating DNs to telemetry device location and serial number is commonly referred to as number administration. 
     At present, DN changes and unpublished DNs are tracked via the service order process and/or direct links to a non-switch database that records customer DNs and address, such as the E 9 11 database. However, delays in database updates, additional interfaces, management of unpublished numbers, the proprietary nature of the service, and E 9 11 databases render this type of tracking inefficient, inaccurate, expensive and never current. 
     SUMMARY OF THE INVENTION 
     The above problems are solved, and a number of technical advances are achieved in the art, by implementing a system and method for a communication system with telemetry device capabilities. The inventive system and method permits a telephone service provider to poll lines served by a switch including those which are flagged as having telemetry devices attached as customer premise equipment (CPE). 
     In accordance with the invention, a system for polling communication lines in a communication system having a plurality of communication lines and at least one telemetry device coupled to one of the plurality of communication lines is described. The system comprises a network switch that creates a polling signal and a network switch transmitter that transmits the polling signal from the network switch to one of the communication lines. A network switch receiver is utilized to receive a reply signal from the one communication line and a processor is employed to determine whether the one communication line is associated with the telemetry device in response to receipt of the reply signal. The processor additionally determines customer identification associated with the telemetry device. 
     Also in accordance with the invention, a method of polling communication lines in a communication system having a network switch, a plurality of communication lines and at least one telemetry device coupled to one of the plurality of communication lines is described. The method comprises the steps of creating a polling signal at the network switch, transmitting the polling signal from the network switch to one of the communication lines, receiving a reply signal from the one communication line and determining whether the one communication line is associated with the telemetry device in response to receipt of the reply signal. The method also includes the step of determining customer identification information associated with the telemetry device. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing advantageous features of the invention will be described in detail and other advantageous features will be made apparent upon reading the following detailed description that is given with reference to the several figures of the drawings, in which: 
     FIG. 1 shows a functional block diagram for the system of the invention with one central office switch; and 
     FIG. 2 is a logical flow diagram showing the process performed by the system of FIG.  1 . 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a block diagram for the communication system  98  having a telemetry application controller  100  in signal communication with a network switch  105 . The network switch  105  is in signal communication with a plurality of network interface units  110 ,  115  and  120  via communication lines  125 . Three network interface units  110 ,  115  and  120  and three communication lines  125 A,  125 B and  125 C are shown for illustration purposes only as it will be appreciated that the present invention may selectively be performed with more or fewer network interface units and communication lines. Each network interface unit is in signal communication with a communication device and a telemetry interface unit (TIU also known as a meter interface unit—MIU), or a communication device only. The TIU is either a individual telemetry device or an interface unit that allows other telemetry units to communicate with the communication lines  125 . Telemetry devices are communication devices that use telemetry signals to communicate with a central office switch. Examples of telemetry devices are TIUs, MIUs, and telemetry units such as telemetry enabled telephone equipment, computers, usage meters, alarms, sensors and display devices. It is appreciated that the telemetry device, TIU and communication device may selectively be different parts of the same component. As an example, a telemetry enabled telephone is both a communication device (it allows voice communication) and a telemetry device or TIU (it allows telemetry data communication) simultaneously. 
     Illustratively, network interface unit  110  is in signal communication with communication device  130  and TIU  135 . Network interface unit  115  is in signal communication with communication device  140 . And network interface unit  120  is in signal communication with communication device  145  and TIU  150 . The network interface units bridge the equipment owned by the telephone service provider to the customer. Thus, each network interface unit is a demarcation point between the network of a telephone service provider and a customer. 
     TIU  135  is in signal communication with a telemetry unit  152  and TIU  150  is in signal communication with a telemetry unit  153 . The telemetry units  152  and  153  are communication devices that receive and transmit telemetry information such as gateways, computers, advanced telemetry telephones and meters (gas, water and electric). Two telemetry units  152  and  153  are shown for illustration purposes only as it will be appreciated that the present invention may selectively be performed with more or fewer telemetry units. TIUs, MIUs and telemetry units are herein referred to as telemetry devices. Communication devices are any devices that allow voice communication, via the communication lines  125 , to the network switch  105 . 
     The network switch  105  contains a polling feature controller  155 , a database  160 , a suppressed ringing telemetry processor  165  and a line termination unit  170 . The line termination unit  170  is an interface unit which interfaces the network switch  105  with the communication lines  125 . The line termination unit  170  contains a network switch transmitter  175  and a network switch receiver  180  which transmit and receive communication signals to and from the communication lines  125 . 
     The telemetry application controller  100  is preferably a computer system located at a telemetry service provider location. A telemetry service provider is a telephone company or third party service provider that renders service to an end customer (i.e. utility company, telephone company or homeowner) by providing a service based on device to device communication and data transfer such as a third party providing remote meter reading and billing service for a public utility company. It is appreciated that the telemetry application controller  100  may also selectively communicate with a telemetry device such as a telemetry enabled telephone in order to determine the parameters (telemetry functions) of the telemetry device. The telemetry application controller  100  preferably requests a polling of communication lines  125  by the network switch  105  and records the results in an application controller database  182 . 
     The network switch  105  is preferably a telephonic switch located a central office such as a 5ESS®-2000 Switch manufactured by Lucent Technologies, Inc. Within the network switch  105 , is the polling feature controller  155  which is a processor that controls the polling actions of the network switch  105 . The polling feature controller  155  polls the communication lines  125  either in response to a request from the telemetry application controller  100  or, independent from the telemetry application controller  100 , based on internal programmed parameters. It is appreciated that these internal programmed parameters may be selectively activated by internal software timers or triggers built or programmed into the network switch  105 . As an example, a DN change would trigger one of these polling sequences. 
     The database  160  is a status database which may be selectively located at the network switch  105 . It is appreciated that the status database  160  may also alternatively be placed at a remote location such as the application controller database  182  and an external telemetry database  183  without changing the procedure described. The database  160  records the results of the polling performed by the network switch  105  and keeps a record of the customer identification information such as associate directory number (DN) or office equipment (OE)/port information on the network switch  105  with the telemetry device(s) serial number, type, TCP/IP sub-addresses, special characteristics (such as processing capability from an onboard processor) service or communication parameters (such as text and messaging services), display type, read only device, data storage, transfer rate and maintenance data storage. The database  160  keeps an effective, accurate and current tracking of customer DNs versus telemetry devices and device type and capability. 
     The polling feature controller  155  polls the communication lines  125  based on a polling rule or command, caused by a DN change, that is preferably provided by the telemetry application controller  100  or the internal software. The polling rule may selectively operate in an update or verification mode. In the update mode, the polling rule requires that the network switch  105  poll the communication lines  125  that have been marked (tagged because DNs cannot be reached) for polling by either the telemetry application controller  100  or the polling feature controller  155  in combination with the database  160 . In the verification mode, the network switch  105  polls all the communication lines  125  and compares the results to the stored values in the database  160 . 
     Additionally, a group polling rule may also selectively be employed by the telemetry application controller  100  or the internal software. A group polling rule selectively polls groups of communication lines  125  for DN changes. 
     The suppressed ringing telemetry processor  165  is a processor that controls the suppressed ringing features of the network switch  105 . The suppressed ringing telemetry processor  165  may selectively be a independent processor on the network switch  105  or part of the switch processor of the network switch  105  as in the 5ESS®-2000 Switch. The suppressed ringing telemetry processor  165  sets up a call path between the network switch  105  and a telemetry device or communication device such as a consumer premise equipment (CPE). The suppressed ringing telemetry processor  165  first sends a polling signal, a single frequency or combination thereof, such as a single of dual tone, a dual tone multiple frequency (DTMF) or a frequency shift keying (FSK) signal, that alerts (wakes up or makes active) the telemetry device without ringing the line connected to the telemetry device. Alternatively, a universal alert signal technique. may be employed. Once the telemetry device is active, the network switch  105  then communicates with the telemetry device. This allows for two way communication between the network switch  105  and the telemetry device without disturbing (ringing) the consumers at the location of the telemetry device or being effected by the features that the consumers may have enabled such as call forwarding, call blocking, automatic recall or other similar features. 
     The universal alert signal is an alert signal (polling signal) that alerts (makes active) any telemetry devices connected to the network switch  105  via the communication lines  125 . The universal alert signal as a universal key and allows a telephonic service provider to communicate with any telemetry devices connected to the network switch  105  without the need to provide password information to the telemetry devices or transmit a specific signal type such as single or dual tone, DTMF or FSK. In response to the universal alert signal, the telemetry devices provide the network switch  105  with non-sensitive information about the telemetry device such as serial number, device type, etc. but not the data itself. It is appreciated that the network switch  105  connects one call at a time through the network switch  105  processor, but several at a time due to to the parallelism in the telemetry devices and communication devices. 
     In response to a polling action by the polling feature controller  155 , the suppressed ringing telemetry processor  165  sends a polling signal (preferably a 480 Hertz tone, however numerous single and dual frequency tones, DTMF, FSK or service provider agreed signal format signals may also be selectively employed), to the communication line. If a telemetry device is present and connected to the communication line the telemetry device will go to an off hook condition in response to the tone within a specified time such as less than one second. As a result of going to an off hook condition the impedance of the telemetry device changes and the new impedance of the telemetry device is detected by the network switch  105  via changes in detected currents or voltages. A reply signal is then transmitted from the telemetry device through the TIU and network interface unit to the receiver  180  of the network switch  105 . It is appreciated that numerous telemetry devices will also communicate with the network switch  105  while still in a on hook (non off hook) condition. These telemetry devices (such as a telemetry enabled telephones) employ circuitry that allows communication with the network switch  105  while still in an on hook state (condition). 
     In response to the reply signal, the polling feature controller  155  will determine that a telemetry device (such as TIU  135 , TIU  150 , telemetry unit  152  and telemetry unit  153 ) is connected to the communication line. the polling feature controller  155  determines that a telemetry device is connected to the network interface because the reply signal is a known alert signal or command, via a single tone, dual tone, FSK, or DTMF signal, that triggers the polling feature controller  155 . The reply signal may selectively be the reflected polling signal in response to the change in impedance value of the telemetry device. The polling feature controller  155  records the DN corresponding to the communication line and instructs the suppressed ringing telemetry processor  165  to communicate with the telemetry device and obtains the information associated with any telemetry unit or units connected to the TIU. 
     Alternatively, if there is no TIU or other telemetry device associated with a network interface unit the network switch  105  will have a time out condition because there is no off hook, or on hook response, at the network switch  105  within the specified time. Alternatively, if there is no response to the first tone, the network switch  105  may selectively cycle through the other tones, DTMF and FSK signals. If there is still no response after the cycle is complete the network switch  105  times out. In response to the time out condition, the polling feature controller  155  determines that there is no telemetry device (such as TIU  135 , TIU  150 , telemetry unit  152  and telemetry unit  153 ) associated to the polled communication line and network interface unit. The polling feature controller  155  then records the information in the database  160  and polls the next communication line. 
     The network switch  105  preferably places polling calls in parallel while processing other calls based on network switch  105  resource load. If the network switch  105  is idle, numerous polling calls may selectively be made at the same time. A real time check at the network switch  105  will determine the polling speed of the network switch  105 . It is appreciated that the network switch  105  is capable of placing many simultaneous polling calls and may selectively cycle though all the communication lines  125  in a limited time. The polling feature controller  155  determines the polling ratio by first looking at the network switch  105  resource utilization. Low resource utilization may selectively permit many simultaneous polling calls. 
     The network switch  105  also supervises the types of calls processed by the network switch  105 . When a incoming or out going call is present on a communication line, the network switch  105  will terminate the polling call on that corresponding communication line. 
     Illustrative of the operation of the communication system  98  polling the communication lines  125 A,  125 B and  125 C, the polling feature controller  155  preferably begins a polling procedure based on an outside request from the telemetry application controller  100  or on internal software logic. The polling feature controller  155  instructs the suppressed ringing telemetry processor  165  to send a polling signal via transmitter  175  to communication line  125 A. When the communication line  125 A receives the polling signal, the communication line  125 A forwards it to the TIU  135  which routs (and selectively interfaces with) the polling signal to telemetry unit  152 . The TIU  135  responds by going to an off hook condition and changing its impedance value within a specified time (for illustration purposes assumed to be less than one second). Alternatively, the telemetry unit  152  may also selectively go off hook in response to the polling signal. As a result, communication line  125 A responds to the receiver  180  with a reply signal preferably within one second. In response to the reply signal, the polling feature controller  155  determines that communication line  125 A has TIU  135  and telemetry unit  152  attached to it because the reply signal may selectively contain a serial number or other identifying information for the TIU  135  or telemetry unit  152 . The pollin feature controller  155  instructs the suppressed ringing telemetry processor  165  to communicate with TIU  135  and telemetry unit  152  and obtain any serial number, class type, device status, TCP/IP sub-addresses, special characteristics, service parameters, display type, read only device, data storage, transfer rate, and maintenance data. The polling feature controller  155  then records, in the database  160  (or database  183 ), the communication line  125 A DN or OE/port information with the corresponding information from the TIU  135  and telemetry unit  152 . 
     Next, the polling feature controller  155  instructs the suppressed ringing telemetry processor  165  to send the polling signal via transmitter  175  to communication line  125 B and to communication device  140  (through network interface unit  115 ). When the communication line  125 B receives the polling signal there is no telemetry device to respond thus there is no reply signal to respond within one second and the polling procedure for communication line  125 B times out. In response to the time out condition, the polling feature controller  155  determines that communication line  125 B does not have a telemetry device attached and polling feature controller  155  records, in the database  160  (or database  183 ), the communication line  125 B DN or OE/port information with a note that there is no telemetry device attached. The procedure for polling communication line  125 C is the same as communication line  125 A. 
     FIG. 2 is a logical flow diagram for the process performed by the system of FIG.  1 . The process starts when the network switch  105  is triggered to poll the communication lines  125  in step  185 . In decision step  190 , if the poll triggering is a result of an external polling request from the telemetry application controller  100 , the process continues to step  195 . In step  195  the polling feature controller  155  receives the polling request from the telemetry application controller  100 . The polling feature controller  155 , in decision step  200 , then determines if the telemetry application controller  100  has permission to make the request. If the answer is NO, the polling feature controller  155  denies permission to the telemetry application controller  100  and the process ends in step  205 . 
     If instead, the answer to decision step  200  is YES, the process continues to step  210 . In step  210 , the polling feature controller  155  receives the service parameters from the telemetry application controller  100  and continues to step  225 . It is appreciated that if the request is made by a telemetry service provider, the telemetry service provider will have permission to look for telemetry devices it owns or controls because the provider preferably identifies who it is and what telemetry devices it is looking to poll. The polling feature controller  155  selectively filters the CPE data to permit sending data that belongs to the service provider. If the network switch  105  is polling to update data records in database  160  or  183 , filtering is not required. Polling rules may also include number of simultaneous calls made, how long should polling take. Polling rules may also request communication lines that have changed to be polled. i.e. look to communication lines tagged by a recent change/verification process. 
     If instead, the answer to decision step  190  is NO, the process continues to step  215 . In step  215 , the polling feature controller  155  receives the polling request from the internal software in the network switch  105  software. In step  220 , the polling feature controller  155  receives the service parameters from the internal software and continues to step  225 . Internal polls are used to update the status database  160  (or database  183 ). Internal polling marks calls for complete polling, selective polling, random polling and speed of polling. 
     In step  225 , the network switch begins to cycle (poll) through the OE terminations associated with each DN. Polling is based on OE number blocks, or load balancing algorithms within the switch based on call processing load. In step  230 , the suppressed ringing telemetry processor  165  then places a suppressed ringing call to each DN, associated with the OE/port, based the polling rule from either the service parameters from the telemetry application controller  100  or the service parameters from the internal software of the polling feature controller  155 . The suppressed ringing call electrical characteristics contain an electrical signal (referred to as a polling signal) that is preferably at a single tone, dual tone, universal tone, DTMF, or FSK signal that is known not to interface with call processing, that travels through the transmitter  175  to the communication lines  125 . In response to the polling signal, the communication lines  125  and any corresponding connected TIUs, telemetry units or other telemetry devices respond by returning a reply signal containing device information (such as identification number, device type, service function parameters) and customer identification numbers to the receiver  180 . In step  235 , the network switch  105  records the telemetry device information and the customer identification numbers on the network switch  105  status database  160  (or database  182 ) and the process continues to decision step  240 . In decision step  240 , the polling feature controller  155  determines, based on whether the polling request was from the telemetry application controller  100  in decision step  190 , whether to send the device information and the customer identification numbers to the telemetry application controller  100 . If the answer is NO, the process continues to step  245  where the network switch  105  resets itself (including resetting timers and triggers) and the process ends in step  205 . 
     If instead the answer to decision step  240  is YES, the process continues step  250 . In step  250 , the polling feature controller  155  sends the device information to the telemetry application controller  100  and the process continues to step  245  where the network switch  105  resets itself (including resetting timers and triggers) and the process ends in step  205 . 
     While the specification in this invention is described in relation to certain implementations or embodiments, many details are set forth for the purpose of illustration. Thus, the foregoing merely illustrates the principles of the invention. For example, this invention may have other specific forms without departing from its spirit or essential characteristics. The described arrangements are illustrative and not restrictive. To those skilled in the art, the invention is susceptible to additional implementations or embodiments and certain of the details described in this application can be varied considerably without departing from the basic principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention are thus within its spirit and scope.