Abstract:
This invention provides a method and apparatus for associating call data with particular users instead of line ports. This call data includes the last incoming and outgoing calls associated with a particular number. This allows the services such as automatic callback, automatic recall, and customer originated trace to be implemented with dynamic line assignment allowing users to maintain the same level of subscribed services at different locations. For mobile users, automatic callback, automatic recall, and customer originated trace can be implemented at the home mobile switching center as well as roaming mobile switching centers. If the mobile user is roaming, updating the call history of the mobile station at the new mobile switching center allows the mobile user to experience seamless services across a large territory.

Description:
FIELD OF THE INVENTION 
     This invention relates to the tracking of call history for wireline users and updating this information at new switches as dynamic line assignment is employed. This invention also applies to mobile users as call history is transferred between mobile switching centers as a mobile user roams. 
     BACKGROUND 
     Currently, there are several services offered by telecommunication providers where previous call history from the line port used by the subscriber is used as input data. Examples of these services include automatic callback, automatic recall, and customer originated trace. The automatic callback service allows a user to place a call to the last party that called the user. The automatic recall service allows a user to place a call to the same number the user last called. And, the customer originated trace allows a user to request an automatic trace of the last incoming call. For these types of services, saving the call history of a user is accomplished by saving the call history data as it relates to a particular line port. 
     There is a need to store call history related to users versus line ports. This is important because certain categories of users may not use the same line ports for subsequent calls. These users include mobile subscribers served via a pool of lines at the central office, wireline subscribers served via pool of lines at the central office where there are many subscribers in relation to a fewer number of ports (possibly for economic reasons in the case of competitive access providers), personal mobility service via wire line phones (smart cards that identify the person on “public” phones), and mobile subscribers on a mobile switching center where line ports are not used. Therefore, a need exists to track and store call history as it relates to a subscriber number rather than a line port. 
     SUMMARY 
     This invention provides a method and apparatus for associating call data with particular users instead of line ports. This call data includes the last incoming and outgoing calls associated with a particular number. This allows the services such as automatic callback and automatic recall and customer originated trace to be implemented without regard to the line port allowing users to maintain the same level of subscribed services at different locations. 
     For mobile users, automatic callback and automatic recall and customer originated trace can be implemented at the home mobile switching center as well as roaming mobile switching centers. If the mobile user is roaming at least two schemes can be deployed for updating the mobile switching center with call history information. First, when the mobile station registers with a mobile switching center, the previous mobile switching center transmits the call history to the new mobile switching center. Second, when the mobile station registers with a mobile switching center, the home location register or the wireless intelligent network obtains the call history information from the previous mobile switching center and transmits this information to the new mobile switching center. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The summary of the invention, as well as the following detailed description of preferred embodiments, is better understood when read in conjunction with the accompanying drawings, which are included by way of example, and not by way of limitation with regard to the claimed invention. 
     FIG. 1 illustrates a prior art block diagram of a switching system with the call history associated with the line ports. 
     FIG. 2 illustrates a block diagram of tracking the call history for an intelligent network node. 
     FIG. 3 illustrates a block diagram of tracking the call history for wireless subscribers via a wireless intelligent network node service control point. 
     FIG. 4 illustrates a block diagram for transferring call history information to the various mobile switching centers. 
     FIG. 5 illustrates a message flow diagram for call origination and termination and the associated updating of call history information for an intelligent network node. 
     FIG. 6 illustrates a message flow diagram for automatic callback service when a user employing dynamic line assignment moves to a new switch. 
     FIG. 7 illustrates a message flow diagram for automatic recall service when a user employing dynamic line assignment moves to a new switch. 
     FIG. 8 illustrates a message flow diagram for call origination and termination and the associated updating of call history information for a wireless intelligent network node. 
     FIG. 9 illustrates a message flow diagram for automatic callback service when a mobile user moves to another mobile switching center. 
     FIG. 10 illustrates a message flow diagram for automatic recall service when a mobile user moves to another mobile switching center. 
     FIG. 11 illustrates a message flow diagram for storing and updating call history information in the mobile switching center/visitor location registry. 
     FIG. 12 illustrates a message flow diagram for a first scheme for transferring call history information to another mobile switching center/visitor location registry. 
     FIG. 13 illustrates a message flow diagram for a second scheme for transferring call history information to the mobile switching center/visitor location registry. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 illustrates a prior art block diagram of a switching system with the call history associated with the line ports. In prior art systems, subscriber telephones  10  are connected via twisted pair lines  12  to line ports  14  located in the switching system  16 . Each line port  14  is connected and associated with a specific subscriber&#39;s telephone line  12 . Call history information is stored in the switching system&#39;s memory and associates call history information such as last called number and last calling number with each line port ID  18 . 
     FIG. 2 illustrates a block diagram of a switching system with an intelligent network based call history. A subscriber&#39;s telephone  20  is connected to a line concentrator  22  containing a plurality of line cards or port via a twisted pair  24 . A line concentrator  22  is an interface that allows low-usage subscriber lines to connect to the high-usage channels. Other telephones  26  and the line concentrators  22  are connected to the switching systems  28  at line ports  31  and  32 . The switching system  28  can store into memory information regarding the tracking of each telephone independent of the line card or port. Each switching system  28  can support a plurality of line ports  30  and  31 . Advanced intelligent network triggers  33  are assigned to each line port  30 . The switching system  28 , as well as other switching systems  37  are connected to an intelligent network node  34 . The intelligent network node  34  assists in the transfer and storage of call history information such as the subscriber ID, last incoming calling dialed number, and the last outgoing called dialed number. 
     For example, as a user  36  disconnects from switching system  28 , the call history information that is associated with a particular subscriber is tracked by the intelligent network node  34  via originating and terminating triggers. As other users  20  attempt to access the switching system  28 , the line port  30  previously used by user  36  is now available to user  20  at the switching system  28 . Since the intelligent network node  34  is tracking the call history of the users and not the line ports, hardware can be optimized across the switching system  28 . 
     FIG. 3 illustrates a block diagram of tracking the call history for wireless subscribers via a wireless intelligent network. When mobile user  38  connects to the mobile switching center (MSC)  40  through the base station  42 , wireless intelligent network triggers are sent to the wireless intelligent network node service control point (WIN/HLR)  44  by the MSC  40 . As the mobile user  38  travels to a point where the mobile switching center  40  terminates service and transfers the service of the user  38  to a different MSC  46 , the WIN/SCP  44  updates the call history and any additional information from the home location register (HLR) to the new MSC  46 . This information is provided to and from the WIN/SCP  44  by originating and terminating triggers. 
     FIG. 4 illustrates a block diagram for transferring call history information to the various mobile switching centers. When a mobile user turns on the cellular telephone (mobile station)  50 , a registration message is sent from the mobile station  50  to the base station  52 . A series of base stations are connected to a MSC  54 . 
     When the mobile user places or receives a telephone call, the call history information is updated in the MSC  54 . When the mobile station  50  moves to the outer range of the MSC  54 , the mobile station  50  registers on the MSC  60  that is closest and capable of supporting the mobile station  50 . The MSC  60  sends a registration message to the WIN/SCP  56 . 
     There are at least two schemes for transferring call history information to the new MSC  60 . First, the WIN/HLR  56  informs the second MSC  60  of the location of the most recent VLR for the mobile station  50  specifying the MSC  54 . The MSC  60  sends a request to the MSC  54  for the most recent VLR and call history associated with mobile station  50 . This information is sent by the MSC  54  to the MSC  60  and MSC  54  deletes the VLR corresponding to mobile station  50 . 
     Second, the WIN/HLR  56  builds a new VLR for the mobile station  50  at the second MSC  60 . A cancellation message is sent from the WIN/HLR  56  to the first MSC  54 . As part of cancellation, the MSC  54  transmits the call history associated with the mobile station  50  to the WIN/HLR  56 . The second MSC  60  receives the VLR including the call history from the WIN/HLR  56 . 
     FIG. 5 illustrates a message flow diagram for call origination and termination and the associated updating of call history information. When a user  100  receives an incoming call from another party on the PSTN  102  and the call is terminated  103  to switch B  106 . Switch B  106  sends a termination message  107  with the calling digits to the intelligent network node  108 . The intelligent network node  108  updates the call history information  111  with the telephone number of the other party who called the user  100 . A trigger response  109  is sent by the intelligent network node  108  to switch B  106 . Switch B  106  terminates the call  110 . 
     When the user  100  originates a call  112 , an origination trigger with the called number  114  is sent by switch B  106  to the intelligent network node  108 . The intelligent network node  108  updates the call history information with the called number  116 . The intelligent network  116  transmits a trigger response to switch B  106  and the origination call  120  is placed on the PSTN  102 . 
     FIG. 6 illustrates a message flow diagram for automatic callback service when a user employing dynamic line assignment moves to a new switch. With dynamic line assignment, a subscriber to a particular set of services has access to those services at different locations. For example, a subscriber who has subscribed to automatic call back service at home, can have that service while on a business trip. When the user  100  from FIG. 5, invokes the automatic call back service at another location, an origination signal  122  is sent to switch A  124 . Switch A  124  transmits an origination trigger  126  to the intelligent network node  108 . The intelligent network node  108  recognizes the automatic call back service code, and retrieves the last incoming dialed number for user  100 . The intelligent network node  108  transmits a trigger response with the last incoming dialed number  128  to switch A  124 . Switch A  124  places the origination call  130  to the last dialed number. 
     FIG. 7 illustrates a message flow diagram for automatic recall service when a user moves to a new switch. When the user  100  from FIG. 7, invokes the automatic recall service at another location, an origination signal  132  is sent to switch A  124 . Switch A  124  transmits an origination trigger  134  to the intelligent network node  108 . The intelligent network node  108  recognizes the automatic recall service code, and retrieves the last outgoing dialed number for user  100 . The intelligent network node  108  transmits a trigger response with the last outgoing dialed number  136  to switch A  124 . Switch A  124  places the origination call  138  to the last dialed number. 
     FIG. 8 illustrates a message flow diagram for updating and tracking call history information in a wireless network. When a mobile user  200  receives an incoming call from another party on the PSTN  202  and the call is terminated  203  to MSC B  204 , MSC B 204  transmits a termination message  207  with the calling digits to the wireless intelligent network node  208 . The wireless intelligent network node  208  updates the call history information  211  with the telephone number of the other party who called the user  200 . A trigger response  209  is sent by the wireless intelligent network node  208  to MSC B  206 . MSC  206  terminates the call  210 . 
     When the user  200  originates a call  212 , an origination trigger with the called number  214  is sent by MSC B  206  to the wireless intelligent network node  208 . The wireless intelligent network node  208  updates the call history information with the called number  216 . The wireless intelligent network  216  transmits a trigger response to MSC B  206  and the origination call  220  is placed on the PSTN  202 . 
     FIG. 9 illustrates a message flow diagram for automatic callback service when a mobile user moves to another MSC. When the mobile user  200  from FIG. 8, invokes the automatic call back service at another location, an origination message  222  is sent to MSC A  224 . MSC A  224  transmits an origination trigger  226  to the wireless intelligent network node  208 . The wireless intelligent network node  208  recognizes the automatic call back service code, and retrieves the last incoming dialed number for user  200 . The wireless intelligent network node  208  transmits a trigger response with the last incoming dialed number  228  to MSC A  224 . MSC A  224  places the origination call  230  to the last dialed number. 
     FIG. 10 illustrates a message flow diagram for automatic recall service when a mobile user moves to another MSC. When the mobile user  200  from FIG. 8, invokes the automatic recall service at another MSC, an origination message  222  is sent to MSC A  224 . MSC A  224  transmits an origination trigger  226  to the wireless intelligent network node  208 . The wireless intelligent network node  208  recognizes the automatic recall service code, and retrieves the last outgoing dialed number for user  200 . The wireless intelligent network node  208  transmits a trigger response with the last outgoing dialed number  228  to MSC A  224 . MSC A  124  places the origination call  230  to the last dialed number. 
     FIG. 11 illustrates a message flow diagram for storing call history information in the mobile switching center/visitor location registry (MSC/VLR). When a mobile user  300  receives an incoming call from another party on the PSTN  302  and the call is terminated  303 , MSC/VLR B  306  stores the last incoming call into the call history information for the mobile user  300 . The MSC/VLR  306  updates the call history information  311  with the telephone number of the other party who called the mobile user  300 . The MSC/VLR  306  terminates the call  310 . 
     When the mobile user  300  originates a call  312 , the MSC/VLR  306  updates the call history information with the called number  314 . The MSC/VLR  306  places origination call  316  to the PSTN  302 . 
     FIG. 12 illustrates a message flow diagram for a first scheme for transferring call history information to another mobile switching center. When the mobile station  300  registers with the new MSC/VLR A  304 , a user ID  317  is sent from the mobile station to the MSC/VLR A  304 . The MSC/VLR A  304  transmits a registration notification message  318  to the home location registry (HLR)  320 . The HLR  320  replies with a registration response  322  including data to build the VLR and the last registered VLR for the mobile station  300 . MSC/VLR A sends a request for call data  324  based on the instructions from the HLR  320  to MSC/VLR B  306 . A call data response message  326  from the MSC/VLR B  306  is sent to the MSC/VLR A  304  with the last incoming and outgoing call data. Once received at the MSC/VLR A  304 , the HLR  320  sends a registration cancellation message  328  to MSC/VLR B  306 . 
     FIG. 13 illustrates a message flow diagram for a second scheme for transferring call history information to the mobile switching center. When the mobile station  300  registers with the new MSC/VLR A  304 , a user ID  330  is sent from the mobile station to the MSC/VLR A  304 . The MSC/VLR A  304  transmits a registration notification message  332  to the home location registry (HLR)  320 . The HLR  320  replies with a registration response  334  including data to build the VLR for the mobile station  300 . The HLR  320  sends a request  336  for call data to the MSC/VLR B  306 . The MSC/VLR B  306  transmits the call data  338  including the last incoming and outgoing calls to the HLR  320 . The HLR  320  forwards  340  this data to the MSC/VLR A  304 . The HLR  320  also sends a registration cancellation message  342  to the MSC/VLR B  306 . 
     While exemplary systems and methods embodying the present invention are shown by way of example, it will be understood, of course, that the invention is not limited to these embodiments. Modifications may be made by those skilled in the art, particularly in light of this disclosure. For example, each of the elements of the disclosed embodiments may be utilized alone or in combination with elements of the other embodiments.