Abstract:
A system and method performs rerouting of an incoming call to a telecommunication services subscriber to provide intelligent network services based on proprietary data about the subscriber&#39;s services. This proprietary data is within the control of the telecommunication service provider&#39;s equipment. Rerouting is performed without providing access to the proprietary data by other telecommunication service providers. Using such a system and method the subscriber&#39;s telecommunication provider can effectively provide intelligent network services without risking dissemination of that proprietary data.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention relates to a system and method for re-directing incoming calls. More specifically, the invention relates to re-directing incoming calls to a provider originating switch to support Intelligent Network (IN) services in public switched telephone networks (PSTN) and Internet protocol (IP) domains. 
     2. Description of Related Art 
     As use of the Internet has grown, subscribers have become interested in receiving the same telephone services over the Internet that they presently enjoy over the PSTN. This has pushed telecommunication providers to provide services to their subscribers which make telecommunication contact easier and better in the Internet realm. 
     As telecommunication service providers seek to provide these new services, new techniques are being developed. For example, a commonly-owned patent, assigned to AT&amp;T Corporation, U.S. Pat. No. 5,473,677, issued on Dec. 5, 1995 to D&#39;Amato et al., which is hereby incorporated herein in its entirety, relates to providing real-time call control within a telecommunications network. Real-time call control is provided using a call selection processor which is separate from the switches that relay the call. The call selection processor responds to in-coming calls and uses information carried in the associated signaling messages to determine what application processor, if any, should be involved on the call. This permits selected calls to be differentiated from other calls so as to allow the selected calls to receive special treatment. 
     In enabling selected calls to be differentiated for special treatment, such features as call waiting have been implemented over the Internet. See, for instance, another commonly-owned patent, assigned to AT&amp;T Corporation, U.S. Pat. No. 5,805,587 (incorporated herein in its entirety), issued on Sep. 8, 1998 to Norris et al., which relates to alerting a service subscriber whose telephone is connected to the Internet of a waiting call via that Internet connection. A waiting call to a subscriber may be forwarded via the PSTN to a services platform, which in turn establishes a connection to the subscriber using the Internet. The platform then notifies the subscriber of the waiting call via the Internet connection. The platform may then forward the telephone call to the subscriber via the Internet responsive to a subscriber request to do so without interrupting the subscriber&#39;s Internet connection. 
     Many subscribers of telecommunication service providers want Caller-ID as well. This is especially true in regard to the use of the service over the Internet. An attempt at providing this type of service was made in U.S. Pat. No. 5,724,412, issued on Mar. 2, 1998, to Srinivasan, which relates to providing a telephone service subscriber with Internet information related to a caller attempting to call the subscriber. Identification information relating to a caller attempting to call the subscriber is provided to the called party via the Internet after a caller has attempted to reach the called party. 
     Thus, Internet enabled IN services such as Internet call waiting, Caller-ID delivery, local number portability, CNAME, etc., have now become commonly available to service subscribers. These are IN services in that the incoming calls receive intelligent routing/treatment. Commonly, telecommunication service providers provide these Internet-enabled intelligent services. Implementing these services often requires access to a telecommunication service provider&#39;s service control point (SCP). This access is provided via a “database dip”. 
     SUMMARY OF THE INVENTION 
     However, when the telecommunication service provider for the subscriber is different than the telecommunication service provider of the caller, who initiated the incoming call that is not a call to an 800 number, providing IN services, e.g., call-waiting, call-forwarding, or caller ID, some degree of access is required to information in the SCP, that is managed by the called party&#39;s telecommunication service provider. Access to such information by other telecommunication service providers is detrimental to the telecommunication service provider because such information is proprietary. Nevertheless, performance of certain IN services require use of that information. Therefore, the telecommunication service provider is faced with a difficult problem of protecting information while having to utilize that information to provide IN services for IP related uses. 
     The present invention provides a solution to such a problem. By providing a system and method that performs re-routing of an incoming call based on proprietary data within the control of the telecommunication service provider&#39;s equipment without having to provide access by other telecommunication service providers, the subscriber&#39;s telecommunication provider can effectively provide service without risking dissemination of that proprietary data. 
     In accordance with an illustrative embodiment of the present invention, an incoming call that requires IN services, such as call-routing or call-waiting, is re-routed to a service provider originating switch (POS) following receipt of the incoming call at the local exchange carrier (LEC) servicing the called subscriber. For example, if a LEC determines that the destination phone number for the incoming call is busy, the LEC reroutes the incoming call to the POS via a specific exchange number. In aPage: 4 more general sense, the service subscriber&#39;s LEC will implement a termination attempt trigger (TAT). This exchange number includes a real exchange number with dummy digits, meaning that there is not a telephone station with such a number, for the rest of the phone number. The POS recognizes that the exchange and dummy digits indicate a re-routed call coming from a LEC to the POS for rerouting using IN services. 
     As a result of this recognition, the POS parks the call and interacts with an SCP that performs a query regarding the called party&#39;s service information. This service information is stored in a database that stores information about the telecommunication subscriber&#39;s service information. As a result of that query, the SCP provides information to the POS on how to re-route the incoming call. Thus for systems that provide Internet Caller-ID Delivery Plus Service, such information may include an alternate phone number or alternate phone numbers which may receive the re-routed call. The SCP information may also include the priority of each of those alternative phone numbers. 
     As a result, the SCP query may not identify an alternative telephone-station to which the incoming call can be completed because, for example, there are no alternative telephone-stations listed in the database or none of the alternative telephone-stations are available to complete the call. In such a case, the SCP may analyze the information in the database to determine whether there is a universal resource locator (URL) where an additional alternative telephone-station or stations may be listed. The SCP then accesses the URL information using a web service control point (WSCP). Such a URL may be updated by the called party at his/her convenience. Such an updatable URL provides the opportunity for the called party to alter his/her information more easily so as to facilitate providing more effective IN services over the IP domain. 
     These and other features and advantages of this invention are described in, or are apparent from, the following description of the apparatus/systems and methods according to this invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various embodiments of this invention will be described in detail, with reference to the following figures, wherein: 
     FIG. 1 shows a diagram of a communication system that provides IN services to a subscriber according to an exemplary embodiment of the invention; 
     FIG. 2 shows a diagram of a data packet format used in conjunction with the exemplary embodiment of the present invention; 
     FIGS. 3 and 4 show flowcharts of the steps in a telecommunication method that provide IN services to a subscriber according to the exemplary embodiment of the invention; and 
     FIG. 5 shows a diagram of a telecommunication system that provides IN services to a subscriber according to an exemplary embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present invention is useful in connection with a method and system for Internet Caller-ID Delivery Plus Service. In such a system, an incoming telephone call is received by a telecommunication service provider&#39;s POS, the telephone call having been routed to the POS by a local exchange carrier (LEC) in the area from which the telephone call was placed. The LEC can route the call to the POS if, for example: 1) the calling party is a subscriber of the telecommunication service provider; 2) the telephone station number called was an 800 number; or 3) the telecommunication service provider has a special arrangement with the LEC. 
     The POS attempts to contact the called party, i.e., the subscriber, via a primary telephone-station and any alternative telephone-station associated with the service subscriber. If attempts to reach the service subscriber via the telephone fail, the POS provides the option of leaving voice-mail for the called party at the primary telephone-station. 
     FIG. 1 illustrates a telecommunication system  100  that provides IN services to a subscriber according to an exemplary embodiment of the invention. FIG. 1 depicts the interrelationship between two different telecommunication service providers  101  and  103  in delivering a call to a called party at any one of a number of telephone-stations  135  or alternative telephone-stations (ATN)  185  or  190  served by the first telecommunication service provider  103 , from a calling party&#39;s telephone-station  105 , served by a second telecommunication service provider  101 . The calling party&#39;s telephone-station  105  is coupled to a LEC  110 , operated by the second telecommunication service provider  101 , via a transmission line  107 . The LEC  110  is also coupled to a switch SW 1   120  via a transmission line  115 . The switch SW 1   120  is owned by a telecommunication service provider other than the first telecommunication service provider  103 . 
     The switch SW 1   120  is also coupled to a LEC  130 , operated by the first telecommunication service provider  103 , via a transmission line  125 . LEC  130  is coupled to the called party&#39;s primary telephone-station (PTN)  135  via a transmission line  137  and coupled to a POS  140  via a transmission line  139 . This primary telephone-station  135  may be any type of telephone-station, e.g., landline telephone-station, cellular telephone-station, beeper, Internet telephone, etc. When the PTN  135  is not available for completion of the telephone call, the LEC  130  re-routes incoming calls to the POS  140  via the transmission line  139 . The LEC  130  may either be operated by the first telecommunication service provider  103  or have some arrangement with the first provider  103  to perform this rerouting. 
     The POS  140  is operated by the first telecommunication service provider  103 . The POS  140  is coupled to an alternate LEC  180  via a transmission line  147 . The alternate LEC  180  is also either operated by the first telecommunication service provider  103  or has some agreement with the first provider  103 . The alternate LEC  180  is coupled to the called party&#39;s alternate telephone-station (ATN)  185  via a transmission line  187  and the ATN  190  via transmission line  189 . The ATNs  185  and  190  may be any type of telephone-station, e.g., landline telephone-station, cellular telephone-station, beeper, Internet telephone, etc. 
     The LEC  130  includes a router (not shown in FIG. 1) which is a software instrument that, under specified conditions, forwards, i.e., triggers, a call to the POS  140 . For example, an incoming call is triggered to the POS  140  if the called party has subscribed to IN services provided by the first telecommunication service provider  103  and the called party&#39;s telephone-station is busy or not answering. The router routes the incoming call to the POS  140  with a dummy exchange number or the like, e.g., 836-0000, to indicate that the call being routed to the POS  140  is subject to IN servicing. 
     The POS  140  is also coupled to an SCP  150  via a transmission line  145  that is an SS 7  signaling path. The SCP  150  contains a database that includes information about the IN services subscribed to by the called party. The POS  140  queries the database of the SCP  150  to determine any alternative telephone numbers for the called party based on the telephone number of the PTN  135  called for the incoming call. The database of the SCP  150  contains the PTN, i.e., the primary telephone-station number dialed by the calling party, and ATNs for the called party. Thus, for example, if the calling party is attempting to reach the called party at the PTN  135 , the POS  140  will find that the service subscriber may have ATNs  185 ,  190  at which he/she may be reached. 
     Further, the database may also contain further information relating to the service subscriber including Internet based routing information, for example, an IP address of a URL that may be accessed using WSCP  160 . The SCP  150  is coupled to the WSCP  160  via a transmission line  157 , which is a signaling path. The WSCP  160  is also coupled to a URL  170  via a transmission line  165 , which is also a signaling path. The URL  170  contains information about additional ATN  190 , besides the ATN  185 , to which an incoming call may be routed through transmission lines  189  or  187 , respectively. 
     When the PTN  135  is dialed, the list of ATNs is retrieved from the SCP  150 . Each of the PTN  135  and the ATN  185  are dialed beginning with the PTN. A line is considered to be unavailable for connection if the call is not answered after a specified number of rings or the telephone station is busy. The incoming call is connected to the first available line. Subsequent to attempting call completion using the PTN  135  and ATN  185  listed in the database of the SCP  150 , any URL  170  information is retrieved from the SCP  150 . The URL information is then retrieved using the WSCP  160  and any resulting additional ATN  190  is used to attempt to complete the call. If the call cannot be completed, the call may be rerouted back to the PTN  135  to leave a voice mail or answering machine message. 
     The primary function of the system  100  is to support the incoming calls to the service subscriber. If a voice connection is available along the transmission line  137 , the LEC  130  will route the call to the PTN  135  on the transmission line  137 . Otherwise, the LEC  130  routes the incoming call to the POS  140  via the transmission line  139 . The POS  140  then routes the incoming call to the SCP  150  which provides instructions to the POS  140  to connect the incoming call to the service subscriber, using one of the provided ATN  185  listed in the database in the SCP  150 . Should subsequent attempts to connect the incoming call using one of the provided ATN  185  fail, the SCP  150  commands the POS  140  to disconnect the caller from the SCP  150  and connect to its Web counter-part WSCP  160 . 
     To accomplish this, the SCP database is populated with a database with records for service subscribers. Each record in the database must have the service subscriber&#39;s PTN as a key column, and may include a list of ATNs  185  in the order desired, such as an office number, to be used to reach the service subscriber. The database record may also include the URL that lists additional information about the service subscriber&#39;s present location. 
     An exemplary embodiment of the invention is preferably used in conjunction with Signaling System Number 7 (SS7) networks. In the SS7 network, a message is sent in the forward direction as part of an ISUP (ISDN user Part) call to set-up protocol. FIG. 2 illustrates the initial address message (IAM)  200  for an incoming telephone call. The IAM  200  is a mandatory message which initiates capture of an outgoing circuit and which transmits address and other information relating to the routing and handling of the incoming call. 
     As shown in FIG. 2, the IAM  200  contains information about the incoming call including the dialed number  210 , the dialing number  220  and a special bit  230 . The dialed number  210  is the called party&#39;s PTN or  135  in FIG.  1 . The dialing number  220  is the calling number information (CNI), also known as calling line identification (CLI). The CNI is the telephone-station number of the calling party  105 , which is sent to the called party for identification purposes. Many service providers also support Caller Name, which transmits the name of the calling party along with the originating telephone number. A special bit  230  is also included that is used in the exemplary embodiment of the invention to indicate that the re-routed incoming call is a re-routed call that has already traversed a POS  140  operated by the telecommunication service provider  103 . When the incoming call traverses the LEC  130 , the special bit  230  is set to indicate that the call is an incoming call that is being sent to a POS operated by the telecommunication service provider  103 . This set special bit  230  also indicates subsequently that the incoming call has already been routed to the POS operated by the telecommunication service provider  103 . 
     FIGS. 3 and 4 illustrate a method for routing an incoming telephone call in accordance with an exemplary embodiment of the invention. 
     The method begins in step  300  and control proceeds to step  305  for receiving a call at a LEC. In step  305 , the incoming call is received at a terminating LEC that is to connect the incoming call to the called party&#39;s PTN and control proceeds to step  310 . In step  310 , the LEC connects the incoming call to the called party&#39;s PTN and control proceeds to step  315 . In step  315 , the LEC determines whether the PTN is available for call completion. If the PTN is available for completion of the incoming call, control proceeds to step  320  in which the LEC completes the incoming call with the PTN and control proceeds to step  415  in FIG. 4, where the method ends. The operation of completing a call is the act of receiving an answer at the telephone-station, thereby eliminating the need for re-routing. 
     Otherwise, control proceeds to step  325  in which the LEC disconnects the incoming call from the PTN, parks the incoming call and sets the special bit  230  in the IAM to indicate that the call is subject to call forwarding. Control then proceeds to step  330  in which the LEC reroutes the incoming call to the POS with a fictitious number using an exchange code of a desired POS (Local Routing Number (LRN)). 
     This routing to the POS is performed by the terminating LEC forwarding the incoming call using a virtual telephone-station number with an exchange code of the desired POS (Local Routing Number (LRN)), e.g., 836, followed by a series of dummy characters, e.g., 0000. Thus, the LEC routes the incoming call to the POS using the virtual telephone number, e.g., 836-0000. 
     Control then proceeds to step  335 . In step  335 , the POS determines whether the IAM relates to an incoming call that has been rerouted from the LEC by analyzing the forwarding number, e.g., 836-6400, used by the LEC to route the incoming call to the POS. If the forwarding number indicates a rerouted incoming call, control proceeds to step  340 . Otherwise control proceeds to step  345  in which non-rerouted calls are processed in a conventional manner and to step  415  in FIG. 4 in which the method ends. 
     In step  340 , the POS then queries the SCP using the PTN information stored in the called party&#39;s information  210  of the IAM  200  as the key and control proceeds to step  350  (of FIG.  4 ). In step  350 , the SCP looks up the alternative routing information in the SCP database and control proceeds to step  355 . For example, the information within the database indicates any services to which the subscriber has subscribed and any ATNs to which incoming calls may be routed, listed in order of priority. In step  355 , the incoming call is connected in accordance with the highest priority ATN information stored in the SCP and control proceeds to step  360 . For example, in step  355 , the incoming call may be connected through a LEC to an ATN. 
     In step  360 , it is determined whether the call can be completed in accordance with the highest priority ATN, e.g., based on the availability of the first alternate telephone-station. If the first ATN is available, control proceeds to step  365  where the call is completed at the first ATN and control proceeds to step  415  where the method ends. Otherwise, control proceeds to step  370  where the incoming call is disconnected from the first ATN and the incoming call is parked. Control then proceeds to step  375 . 
     Step  375  determines whether additional ATNs are listed in the SCP database and may be used to forward the incoming call. If additional ATNs are available, control proceeds to step  330  in FIG. 3 for routing based on the remaining ATN information. Steps  330 - 375  are performed for the ATNs listed in the SCP database in order of priority. If during the call-forwarding of steps  330 - 375 , the incoming call is completed, control proceeds to step  415  where the method ends. 
     Otherwise, control proceeds to step  380  in which it is determined whether a URL field in the database identifies a URL that contains information about the present location of the subscriber, such as further alternative telephone numbers. If the field fails to indicate a URL, control proceeds to step  410  where the incoming call is routed to the PTN so that the calling party may leave an answering machine message or voice-mail, if those are options or services offered by the called party. Control then proceeds to step  415  where the method ends. 
     If the field indicates a URL, control proceeds to step  385 , in which the ATN information at the URL are returned for use in call-forwarding. Control then proceeds to step  390 . In step  390 , the incoming call is routed to a LEC and connected to the highest priority ATN based on the information at the URL, e.g., information about the subscriber&#39;s present location. Control then proceeds to step  395  in which it is determined whether the highest priority ATN is available. If the ATN is available, control proceeds to step  400  where the call is completed at the ATN and control proceeds to step  415  where the method ends. Otherwise, control proceeds to step  405  where the incoming call is disconnected from the ATN and the incoming call is parked. Control then proceeds to step  410  where the POS routes the incoming call to the PTN so that the calling party may leave an answering machine message or voice-mail, if those are options or services offered by the called party. Control then proceeds to step  415  where the method ends. 
     FIG. 5 shows a telecommunication system  500  that provides IN services to a subscriber according to another exemplary embodiment of the invention. Unlike FIG. 1, FIG. 5 actually depicts the telecommunication system structure operated by a single telecommunication service provider  503 . Thus, in FIG. 5, an incoming call is delivered from a calling party&#39;s telephone-station  505  to a called party served by the same telecommunication service provider  503 . The calling party&#39;s telephone-station  505  is coupled to a LEC  510  via a transmission line  507 . 
     The LEC  510  is also coupled to a POS  540  via a transmission line  517 . The POS  540  is also coupled to a LEC  530  via a transmission line  527  and a LEC  580  via a transmission line  577 . Each of LEC  530  and LEC  580  is either operated by the telecommunication service provider  503  or has some agreement with the service provider  503  to perform rerouting for IN services. LEC  530  is coupled to the called party&#39;s telephone-station  535  via a transmission line  537 . LEC  580  is coupled to the called party&#39;s ATN  585  via a transmission line  587 . These telephone-stations  535  and  585  may be any type of telephone-station, e.g., landline telephone-station, cellular telephone-station, beeper, Internet telephone, etc. 
     The POS  540  is operated by the telecommunication service provider  503  that provides services to which the incoming call is directed. The POS  540  is coupled to an SCP  550  via a transmission line  547 . The SCP  550  is also coupled to a WSCP  560  via a transmission line  557 . The WSCP  560  is also coupled to a URL  570  via a transmission line  567 . The URL  570  contains information about additional ATNs  590 , besides the telephone-station  585 , to which an incoming call may be routed through transmission lines  589 . 
     IN services are provided to a subscriber in the architecture illustrated in FIG. 5 in a method very similar to how IN services are provided in the architecture of FIG.  1 . However, one significant difference is that the LEC  530  does not set the special bit  230  in the IAM of FIG.  2 . This is because the incoming call has already traversed the POS  540  before the incoming call reaches the LEC  530 . Therefore, before the LEC  510  routes the incoming call through the POS  540 , the LEC  510  sets the special bit  230  in the IAM  200  to indicate that the incoming call has been routed through the POS  540  and the POS  540  in turn routes the incoming call to the terminating LEC  530  of the PTN  535 . The remaining methodology for forwarding the incoming call using the system  500  is similar to that illustrated in FIG.  1  and described in conjunction with FIGS. 3 and 4. 
     While the present invention has been described with reference to specific embodiments, it is not confined to the specific details set forth but is intended to cover such modifications or changes as may come within the scope of this invention. 
     While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. 
     For example, the relationship between the alternative telephone-station  185  and the POS  140  may be altered. Specifically, it is foreseeable that the ATNs  185  or  190  may be coupled to the first LEC  130  rather than the second LEC  180 . 
     Additionally, the SCP or URL may include IP address information for the subscriber so that an electronic mail message may be left at the address indicating information about the call that was not completed. Such information may include an electronic message from the called party. 
     Also, Page: 15 although the operation of the present invention has been explained using the application of providing Caller-ID delivery, it is foreseeable that other triggers besides termination attempt trigger (TAT) may be used to cause re-routing, for example, when providing call-forwarding on receipt of a busy signal. 
     Accordingly, the exemplary embodiments set forth herein are intended to be illustrative, not limiting. Various alterations may be made without departing from the spirit and scope of the invention.