Patent Publication Number: US-2007121877-A1

Title: System for managing the addition of a call waiting party to an existing subscriber call connection

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is related to a U.S. Patent application titled “System For Managing The Transfer Of A Call Waiting Party Into An Existing Subscriber Call Connection To Replace A Subscriber Station On The Existing Call Connection” and filed on the same date as the present application.  
     FIELD OF THE INVENTION  
      This invention relates to communication networks and the management of existing subscriber station call connections with respect to call waiting call parties.  
     BACKGROUND OF THE INVENTION  
      It is a problem in the field of communication networks to enable a subscriber, who is a call waiting party on an existing subscriber station call connection, to be included with the two parties on the existing subscriber station call connection.  
      Presently, when a party who is on an existing subscriber station call connection has a third party in a call waiting mode, there is no ability to enable the call waiting party to be included with the two parties on the existing subscriber station call connection. The addition of another (third) party into an existing subscriber station call connection can only occur in the present telephone network in the form of one of the two parties on the existing subscriber station call connection initiating Three Way Calling and calling the third party. The Three Way Calling feature adds the third party to the existing subscriber station call connection but cannot respond to a third party calling in to one of the two parties on an existing subscriber station call connection. Therefore, the existing communication network is unable, in an existing subscriber station call connection with a call waiting party, to enable the call waiting party to be included with the two parties on the existing subscriber station call connection.  
     BRIEF SUMMARY OF THE INVENTION  
      The above-described problems are solved and a technical advance achieved by the present System For Managing The Addition Of A Call Waiting Party To An Existing Subscriber Call Connection, herein termed “system for adding a call waiting party to an existing call connection”. This system enables a party on the existing subscriber station call connection who receives an incoming call from a third party to add the calling party to the existing subscriber station call connection.  
      The system for adding a call waiting party to an existing call connection operates when an incoming call is directed to one of the parties on the existing call connection. The called party receives an indication of the incoming call and flashes to place the other party on the existing call connection on hold and also to pick up the incoming call. After speaking with the calling party, the called party determines that the calling party should communicate with both the called party and the other party on the existing call connection. The called party then operates their phone by inputting specific digits or a code to activate the system for adding the call waiting party to an existing call connection which responds by maintaining the existing call connection and also adding the calling party to the existing call connection. All three parties are then on the call connection and continue to converse until one of the three parties disconnects from the call, creating the billing record and releasing the call resources.  
      The call remains up until either party disconnects. There is also the possibility of another incoming call (call waiting) that is desired to be added or not. This also allows for normal Three Way Calling to occur after the disconnecting of one of the parties.  
      If the called party hangs up, then it would be subject to any consequence of a Three Way Call. In this case, the two other parties would be dropped or the call could be “transferred” to the other two parties. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  illustrates, in block diagram form, the overall architecture of a telephone network and a typical call connection that uses the present system for adding a call waiting party to an existing call connection; and  
       FIG. 2  illustrates, in flow diagram form the operational steps taken by the present system for adding a call waiting party to an existing call connection to implement a call transfer for a subscriber station. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       FIG. 1  illustrates, in block diagram form, the overall architecture of a telephone network and a typical call connection that uses the present system for adding a call waiting party to an existing call connection; and  FIG. 2  illustrates, in flow diagram form, the operational steps taken by the present system for adding a call waiting party to an existing call connection to implement a call transfer for a subscriber station.  
      The communications network comprises a traditional voice communications network that includes a plurality of local communications systems. This could be a PSTN land configuration, wireless configuration, or a combination of the two  101 C,  102 C, such as telephone switching systems that are part of the Public Switched Telephone Network (PSTN)  100  and are interconnected via trunk circuits (this could be an IP connection as well) to an Inter-Exchange Carrier System (IXC)  103 . Each of the communications systems  101 ,  102  serve a plurality of terminal devices, and the communications systems  101 ,  102  maybe interconnected via an out-of-band signaling link CS through the Inter-Exchange Carrier System (IXC)  103 , using the well-known SS7 signaling protocol This could also be using the IP protocol as well. The operation of such a communications network is well known and is not described in detail herein. The communications systems  101 ,  102  provide a set of features and services to the terminal devices that they serve, including a system for adding a call waiting party to an existing call connection wherein the communications systems  101 ,  102  implement the call connection function for the associated terminal devices in response to control signals that are received from the terminal devices. In addition, the communications systems  101 ,  102  are both equipped with the system for transferring a call connection to a call waiting party CHN 1 , CHN 2  that are operational in the controllers  101 C  102 C of the respective communications systems  101 ,  102 .  
      For the purpose of illustration, the call connection used to describe the operation of the present system for transferring a call connection to a call waiting party CHN 2  consists of terminal device  111  connected to terminal device  122 . The connection extends from terminal device  111  through communication system  101  (path  1 ), Inter-Exchange Carrier System (XC)  103  (path  2 ), communication system  102  (path  3 ), to terminal device  122 . The use of multiple communication systems and the Inter-Exchange Carrier System (IXC) for the call connection is not a limitation on the operation of the system for transferring a call connection to a call waiting party CHN 2 , since the call connection can be solely within communication system  102 , or may include one or more mobile terminal devices and their associated Mobile Switching Centers (not shown).  
      In this environment, the only way to add a third party to the existing call connection or to substitute a third party for one of the two parties on the existing call connection is to use the Three Way Calling feature. The Three Way Calling feature is initiated when one of the two parties (first party on the existing call connection flashes the switch hook to place the other party on hold and initiates a call to the third party. The third party is then connected to the first party, who can again flash the switch-hook to add the third party to the existing call connection. Unfortunately, this feature is only outbound capable, in that one of the two parties on the existing call connection is the only one who can contact the third party.  
      The system for transferring a call connection to a call waiting party CHN 2  operates to enable a third party (calling part to contact one party on an existing call connection and be added to the existing call connection. This process is initiated when an incoming call from calling party located at terminal device  121  is directed to the terminal device  122  of one of the parties on the existing call connection (paths  1 - 3 ) at step  201 . The called party receives an indication of the incoming call on their terminal device  122  at step  202  and flashes the switch hook of their terminal device  122  at step  203  to place the terminal device  111  of the other party on the existing call connection on hold and also to pick up the incoming call from the calling party by connecting the terminal device  121  of the calling party to the terminal device  122  of the called party over path  4 . After speaking with the calling party, the called party at step  204  determines that the calling party should communicate with both the called party and the other party on the existing call connection. The called party then operates their terminal device  122  at step  205  by inputting specific digits or a code to activate the system for adding the call waiting party to an existing call connection CHN 2 , which responds by maintaining paths  1 - 3  of the existing call connection while adding the terminal device  121  of the calling party to the existing call connection via path  5  at step  206  and dropping path  4  at step  207 .  
      All three parties are then on the call connection and continue to converse until one of the three parties disconnects from the call at step  208 , creating the billing record and releasing the call resources at step  209 .  
     SUMMARY  
      The system for adding a call waiting party to an existing call connection enables a party on the existing subscriber station call connection who receives an incoming call from a third party to add the calling party to the existing subscriber station call connection.