Abstract:
A method and system are disclosed for automated call back of a first telephone station that has been placed on hold by a second telephone station in an advanced intelligent network. The system comprises a service switching point connected to the first telephone station, a service node adapted to connect the second telephone station with the first telephone station when the second telephone station becomes available, and a service control point containing a database identifying the service node as adapted to connect the second and first telephone stations. The method includes the following steps: at the service switching point forwarding a request to the service control point to identify one of the plurality of service nodes to handle an automated call back from the second station to the first station; searching the database at the service control point for one of the plurality of service nodes to handle the automated call back to the first station from the second station; identifying to the service switching point, one of the plurality of service nodes to handle the automated call back from the second station to the first station; forwarding to the service node a request for automated call back from the second station to the first station; and upon receiving a signal from the second station at the service node, connecting the second station and the first station.

Description:
FIELD OF THE INVENTION 
   The present invention generally relates to the field of telecommunications and to an apparatus and method for managing telephony-based services. More particularly, the present invention relates to an intelligent or advanced application, such as an Advanced Intelligent Network (AIN) application, for automated on-hold call back within a telephone network. 
   BACKGROUND OF THE INVENTION 
   In conventional telephone networks, often one party to a telephone connection is placed on hold by a second party. In such cases, the party that has been placed on hold is required to stay on the line and wait to be serviced. While holding on the line, the party is not available to apply themselves to other activities but rather must remain attentive to the phone line in case the call is taken off of hold. Thus, during the period that a party is on-hold, he/she is often underutilized and certainly is not entirely free to involve themselves in other activities. 
   In recent years, a number of new telephone service features have been provided by an AIN. The AIN evolved out of a need to increase the capabilities of the telephone network architecture in order to meet the growing needs of telephone customers or users. The AIN architecture generally comprises two networks, a data messaging network and a trunked communications network. The trunked communications network handles voice and data communications between dispersed network locations, whereas the data messaging network is provided for controlling operations of the trunked communications network. 
   While prior telephone systems have addressed numerous shortcomings in the art, they have failed to address the requirement that a party, who has been placed on hold, must stay on the line and wait to be serviced. It would be highly desirable if the party that has been placed on hold could hang up and automatically be notified when the other party becomes available. The present invention is directed to such a solution. 
   SUMMARY OF THE PRESENT INVENTION 
   According to an aspect of the invention, there is provided a system for automated on-hold call back within a telephone network. The system provides that when a first telephone station is placed on hold by a second telephone station, the operator of the first station may hang up and will be automatically notified when the operator of the second telephone station becomes available. The system includes a service switching point communicating with at least the first telephone station, a service node communicating with the service switching point, and a service control point which contains a database. The service node is adapted to connect the second telephone station with the first telephone station when the operator of the second telephone station becomes available. The service control point database identifies that the service node is adapted to connect the first and second telephone stations. 
   In accordance with another aspect of the invention, there is provided a method of automated call back from a second telephone station to a first telephone station in an advanced intelligent network comprising the following components: a service switching point connected to the first station; a plurality of service nodes each having an interactive data system; and a service control point containing a database. The method includes the following steps: at the service switching point forwarding a request to the service control point to identify one of the plurality of service nodes to handle an automated call back from the second station to the first station; searching the database at the service control point for one of the plurality of service nodes to handle the automated call back to the first station from the second station; identifying to the service switching point, one of the plurality of service nodes to handle the automated call back from the second station to the first station; forwarding to the service node a request for automated call back from the second station to the first station; and upon receiving a signal from the second station at the service node, connecting the second station and the first station. 
   According to yet another aspect of the invention, there is provided a method of on-hold call back in a telephone network, comprising the following steps: receiving a request for on-hold call back wherein the request identifies a first telephone station and a second telephone station; at a service node, calling the first telephone station and indicating to a first telephone station operator that the on-hold call back has been initiated and directing the first telephone station operator to hang up; at a service node, broadcasting a message to the second telephone station indicating to a second telephone station operator that the first telephone station has requested a call back; at the service node, upon receipt of a signal from the second telephone station indicating that the second telephone station operator is available, calling the first telephone station to notify the first telephone station operator that the second telephone station operator is available; if the first telephone station operator is available, connecting the first telephone station and the second telephone station. 
   The above-listed features of the present invention will be more fully set forth hereinafter. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is further described in the detailed description that follows, by reference to the noted plurality of drawings by way of non-limiting examples of preferred embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein: 
       FIG. 1  illustrates, in a general block diagram form, an Advanced Intelligent Network (AIN)-based system for implementing intelligent network management features, in accordance with an embodiment of the present invention; 
       FIGS. 2A-B  illustrate an exemplary flow diagram of call processing, according to an aspect of the present invention; and 
       FIG. 3  illustrates an exemplary flow diagram of call processing, according to another aspect of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   According to an aspect of the present invention, an apparatus and method for on-hold call back may be implemented using an AIN or AIN-type network. AIN systems are described in U.S. Pat. No. 5,701,301, which is incorporated herein by reference in its entirety. In particular, an AIN network with advanced intelligent network capabilities may be utilized to implement the various features and aspects of the invention. It should be noted, however, that the implementation of the present invention is not limited to AIN-based networks and other advanced or intelligent networks and arrangements may be used to implement the invention. 
   Referring now to the accompanying drawings,  FIG. 1  illustrates a simplified AIN-based network arrangement incorporating the various features of the invention, as further described below. In the embodiment of  FIG. 1 , the system includes a first telephone station which for illustrative purposes will be referred to as subscriber station  110  and a second telephone station referred to as third party station  112 . Stations  110  and  112  have corresponding switches, e.g., service switching points (SSP) (also known as central offices (CO))  114  and  116 . The COs  114  and  116  may comprise, for example, 1AESS or 5ESS switches. These switches may be manufactured by, for example, Lucent Technologies, Inc. or Nortel. 
   In the example shown in  FIG. 1 , each switch may include different types of facilities and/or triggers. SSPs  114  and  116  are each programmable switches which perform the following functions: recognize AIN-type calls, launch queries to service control point (SCP)  118 , and receive commands and data from SCP  118  to further process and route AIN-type calls. When one of SSPs  114 ,  116  is triggered by an AIN-type call, the triggered SSP formulates an AIN service request and responds to call processing instructions from the network element in which the AIN service logic resides. According to an aspect of the invention, the AIN service logic may reside in a database at SCP  118 . 
   As further shown in  FIG. 1 , SSP  114  is connected to SSP  116  over trunk  120 . Trunk  120  may be either a SS7 controlled inter-machine trunk (IMT), or primary rate interface (PRI) trunk and the type of trunk will be in accordance with both the sending and receiving SSP to which it is connected. If either of SSPs  114 ,  116  is a 1AESS type switch, the trunk will be an SS7 controlled IMT type trunk as the 1AESS is not capable of supporting PRI trunks. However, if both the sending and receiving switches are either a DMS-100 switch or a 5ESS switch, the trunk may be either an SS7 controlled IMT type trunk or PRI type trunk. 
   AIN SSPs  114  and  116  may allow normal switch processing to be suspended at specific points in a call so that the switch may send an AIN message query via signaling transfer point (STP)  120  to SCP  118 . SCP  118  may execute software based service logic and return call-processing instructions to the triggering AIN SSP. New services may be provisioned by assigning AIN SSP triggers to customer lines, trunks, and/or NANP telephone numbers. 
   SCP  118  may comprise an integrated service control point (ISCP). The ISCP is an integrated system that may include a service management system (SMS  122 ), a data and reports system (DRS)  124 , a programmable service control point (SCP) (not shown), and a service creation environment (SCE) (not shown). The SCE may be provisioned as a terminal implemented to work with SMS to create, modify, and load services into the SCP database. The SCE may comprise, for example, a programming environment (such as SPACEK) for creating and provisioning services. SCP  118  may execute software-based service logic and return call routing instructions to triggering SSPs  114  and  116 . SMS  130  may be provided for administrative purposes to synchronize customer CPR and data on the mated pair of ISCPs that SCP  118  represents. DRS  124  may be provided for compiling call information to be used for billing and administrative purposes. 
   The system of  FIG. 1  further comprises service node (SN)  134 . SN  134  is an interactive data system that acts as a switch to transfer calls. SN  134  provides interactive help, collects voice information from participants in a call, and provides notification functions. SN  134  may be a Lucent Technologies Star Server FT Model 3200 or Model 3300, although others may be employed without departing from the scope of the invention. 
   In order to facilitate signaling and data messaging, each SSP  114  and  116  is equipped with Common Channel Signaling (CCS) capabilities, e.g., SS7, which provides two-way communications of data messages over CCS links  150 ,  152 ,  154 ,  156 ,  158 , and &#39;160 between components of the AIN network. The data messages may be formatted in accordance with the Transaction Capabilities Applications Part (TCAP). Alternatively, ISDN Users Part (ISUP) may be used for signaling purposes between, for example, SSPs  114  and  116 . In such a case, SSPs  114  and  116  may be equipped with the capability to map appropriate data between TCAP and ISUP protocols, and vice versa. The telephone network essentially employs an upper-level software controlled network through the STPs and the SCP (and/or ISCP). The software presides over the hardware to check the call route and the availability of connection prior to hardware connection. 
   Accordingly, the connections by links  150 ,  152 ,  154 ,  156 ,  158 , and  160  are for signaling purposes and allow SSPs  114  and  116  to send and receive messages to and from SCP  118  and SN  134  via STP  120 . For purposes of illustration, various features of the present invention will now be described from the standpoint of a switch implementing AIN protocols, and the CPR provisioned with TAT,  10 D or DLN triggers. However, one skilled in the art will recognize that the above-described network is a simplified network meant for explanatory purposes. It is likely that a telephone network may comprise numerous user stations, SSPS, STPs, SCPs, and SNs along with other telephone network elements. 
   According to one aspect of the invention, a system for providing an on-hold call back service within the AIN or AIN-type environment is provided. Requests for on-hold call back are serviced by the AIN telephone network such that a party to a telephone connection that has been placed on hold can hang-up and be notified when the other party becomes available to take the call. For example, if subscriber station  110  is placed on hold by third party station  112 , the operator of subscriber station  110  may hang-up and SSP  114  cooperates with SCP  118  and SN  134  to notify subscriber station  110  when the operator of third party station  112  becomes available. 
   Referring now to the  FIGS. 2A and 2B , there is illustrated an exemplary overview of the call flow logic according to an aspect of the present invention. The call flow for the on-hold call back service begins when, at step  300 , an operator at subscriber station  110  places a call to third party station  112 . The call is routed over the telephone network via normal procedures. At step  302 , the call from subscriber station  110  is placed on hold by the operator of third party station  112 . The operator of subscriber station  110 , having been placed on hold, invokes the on-hold call back service at step  304 . The on-hold call back feature may be invoked, for example, by flashing the switch hook at subscriber station  110 , which has the effect to place third party station  112  on hold. Thereafter, the operator of the subscriber station  110  may enter a feature code such as, for example, * 99  to signal that the on-hold call back service is being requested. 
   It is also a feature of the present invention that the party which requests the on-hold call back service, may also request that during the period which they are on-hold waiting for the other party, they be periodically polled as to whether they wish to continue waiting on-hold. Thus, the operator of subscriber station  110  may also request that the system periodically poll the operator as to whether to continue waiting for third party station  112  to respond. Typically this request is made in response to prompts from the system. Generally, the frequency of the polling is specified by the telephone company. For example, a telephone company may specify that polling occurs every 15 minutes for a maximum of one hour. 
   At step  310 , SSP  114  detects the request for the on-hold call back service. In response to the request, at step  312 , SSP  114  initiates a customized dialing plan (CDP) trigger associated with the on-hold call back feature. At step  314 , the CDP trigger causes a TCAP message to be routed to SCP  118  via STP  120  wherein the message includes a CDP query to be processed by SCP  118 . The CDP query is directed to identifying a service node (SN) to handle the on-hold call back request. In one embodiment, the selection of an SN to handle the request is determined by the telephone station from which the call back is to be made. In the present example, the on-hold call back is to be placed from third party station  112 . Accordingly, the CDP query contains information identifying third party station  112 . 
   At step  316 , SCP  118  receives the CDP query and at step  318 , SCP  118  responds to the query by launching a logic program which is referred to herein as a service package application (SPA). The SPA queries a database located at SCP  118  using the information contained in the CDP query. Specifically, the application uses the information identifying the third party station  112  to resolve which service node will handle the on-hold call back. In the present example, the database at SCP  118  designates SN  134  as responsible for handling on-hold call back from third party station  112 . Typically, SN  134  is identified by a unique identifier such as a directory number (DN). The DN identifies a multi-line hunt group which connects SSP  110  to SN  134 . The DN is stored as a 10 digit telephone number in the SCP  118  database. At step  320 , SCP  118  transmits a TCAP message comprising instructions for handling the on-hold call back request to SSP  110 . The instructions include a DN identifying SN  134  as being operable for handling the call-back feature. 
   At step  322 , SSP  110  extracts the service node identifier, i.e. DN, from the instructions and at step  324  places a call to SN  134 . At step  326 , SN  134  accepts the call from SSP  110 . This has the effect of placing SN  134  in communication with subscriber station  110 . At step  328 , SN  134  broadcasts a message that the on-hold call back is being implemented to subscriber station  110  and directs the operator of subscriber station  110  to hang up. In response, at step  330 , the subscriber station operator hangs up. 
   At step  332 , SN  134  broadcasts an announcement to third party station  112  indicating that subscriber station  110  called and requested that the operator of the third party station  112  call back. The announcement further provides direction as to how to implement the call back. For example, the announcement may direct an operator of the third party station to “press any key to notify the caller that you are now ready to speak with them.” While broadcasting this message to third party station  112 , SN  134  simultaneously listens for input from third party station  112  identifying that the third party station operator has become available. 
   If at step  334 , a response is received at SN  134  from third party station  112 , at step  336  SN  134  places a call to subscriber station  110 . If at step  338 , the call is answered at subscriber station  110 , at step  340  SN  134  detects that the call has been answered and transfers the third party call to subscriber station  110 . Thereafter, at step  342 , the operators of subscriber station  110  and third party station  112  are free to converse. Of course, if at step  338 , the call is not answered, at step  344  SN  134  broadcasts a message to third party station  112  indicating that the operator of subscriber station  110  is no longer available. 
   It should be noted that according to one aspect of the invention, it is a feature of the system that a time limit be set beyond which SN  134  will discontinue broadcasting a message to third party station  112 . If no response is received within the prescribed time period, the callback will be canceled. Thus, if at step  334 , no response has been received in the time interval, at step  350 , SN  134  determines whether the predetermined maximum time period has been exceeded. If, at step  350 , the time limit has been exceeded, at step  352 , SN  134  discontinues broadcasting the announcement to third party station  112  and terminates the connection to third party station  112 . At step  354 , SN  134  places a call to subscriber station  120  and broadcasts a message indicating that the requested call back has timed out. 
   As noted above with reference to step  302 , it is also a feature of the system that when the on-hold call back feature is requested, the operator may request that the system periodically check with the requester as to whether he/she wishes to continue waiting for the call back. In an exemplary embodiment, the requester may be polled, for example, every 15 minutes. Thus, if at step  350 , the maximum waiting period has not been exceeded, at step  360 , SN  134  determines whether the time interval for periodic polling of the subscriber has expired. If so, at step  362 , SN  134  places a call to subscriber station  110  and broadcasts a message indicating that the periodic interval has expired and requests input as to whether to continue to hold. If at step  364 , the line to subscriber station  110  is busy, it is assumed that the subscriber wishes to continue with the on-hold call back and flow continues at step  332 . If the line is not busy, and at step  366  the subscriber does not answer, at step  368 , SN  134  terminates the call-back feature. If the subscriber does answer, and at step  370  SN  134  receives an input from the subscriber station indicating the operator of subscriber station  110  desires to continue on hold, SN  134  continues to =broadcast the announcement to third party station  112 . If however, at step  370 , SN  134  receives an input indicating a desire to discontinue the on-hold call back, at step  372 , SN  134  terminates the connection to third party station  112 . 
   According to still another feature of the present invention, a subscriber who has requested to implement the on-hold call back feature might also cancel the request. For example, the operator of subscriber station  110  may have been placed on-hold by third party station  112  and requested to be called back. However, before the call back is implemented, the operator of subscriber station  110  may decide to cancel the request.  FIG. 3  depicts the call flow logic for the cancellation procedure. At step  400 , the operator of subscriber station  110  signals to cancel a previously requested on-hold call back. The operator may signal to cancel the feature by pressing a predefined combination of keys at subscriber station  110 . For example, the operator may signal by pressing * 89 . 
   At step  402 , SSP  114  receives the request to cancel the call back and at step  404  SSP  114  initiates a CDP trigger corresponding to a request to cancel on-hold call back. At step  406  the CDP trigger causes a query to be transmitted to SCP  118 . The query includes information identifying that the call back is to take place from third party station  112 . In response to the query, at step  408  SCP  118  launches a logic application that queries the database to identify the SN designated to handle call backs from third party station  112 . Of course, in the present illustrative example, SN  134  handles callbacks from third party station  112  and is therefore identified in the database. Thereafter, at step  410 , SCP  118  transmits a response to SSP  110  wherein the response identifies SN  132 . At step  412 , SSP  110  transmits a request to SN  134  to cancel the call back from third party station  112  to subscriber station  110 . The request identifies subscriber station  110  and third party station  112 . At step  414 , SN  134  terminates the connection with third party station  112 . 
   As described above, the present invention provides a system for on-hold call-back. The system allows persons that have been placed on hold to hang up and be notified when the other party becomes available. Thus, the system frees persons from having to remain on the phone line waiting for the party that placed them on hold. Users of a system in accordance with the invention, therefore, can apply themselves to other activities while the system remains attentive to when the second party becomes available. In this way, a system in accordance with the present invention provides the potential to increase worker productivity. 
   It is noted that the written description provided herein contains acronyms which refer to various communication services and system components. Although known, use of several of these acronyms is not strictly standardized in the art. For purposes of the written description herein, acronyms will be defined as follows:
     10D—10 Digit Trigger   AIN—Advanced Intelligent Network   CCIS—Common Channel Interoffice Signaling   CCS—Common Channel Signaling   CO—Central Office   CPR—Call Processing Record   CPN—Calling Party Number   DLN—Dialed Line Number   DRS—Data and Reports System   EO—End Office   IMT—Inter-machine Trunk   ISCP—Integrated Service Control Point   ISUP—ISDN Users Part   LATA—Local Access and Transport Area   NANP—North American Numbering Plan   NPA—Numbering Plan Area   NXX—Central Office Code   PRI—Primary Rate Interface   PSTN—Public Switched Telephone Network   SCE—Service Creation Environment   SCP—Service Control PointSMS—Service Management System   SS7—Signaling System 7   SSP—Service Switching Point   STP—Signaling Transfer Point   TAT—Termination Attempt Trigger   TCAP—Transaction Capabilities Applications Part   TG—Trunk Group   TN—Telephone Number   

   It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the invention has been described with reference to preferred embodiments, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitations. Further, although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein; rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. Those skilled in the art, having the benefit of the teachings of this specification, may effect numerous modifications thereto and changes may be made without departing from the scope and spirit of the invention in its aspects.