Telephone call dialling

Abstract

A communications device such as a mobile telephone responds to the input of a dialed number for a call destination by generating and outputting a request message transmitted to a control center by a telecommunications system. The device receives a response message from the control center containing routing data and credit data representing remaining credit within an account limit of the subscriber. An outgoing communications session is then initiated using the routing data which may for example enable a dialed telephone number to be modified to achieve optimum routing to the call destination by one or more preferred networks. The device also includes a credit control application for limiting the duration of the communication in accordance with the credit data. Mobile telephones may thereby be used with a prepayment subscription account even during a roaming operation in which the mobile telephone registers with a network other than the subscriber's home network.

1 . A device for communication in use with a call destination via a telecommunications system using a credit controlled subscription account, the device comprising; 
 input means for receiving input data defining the call destination;    message generating means for generating a request message comprising the input data;    output means operable to output the request message in use to a control centre;    receiving means operable to receive in use from the control centre a response message comprising routing data defining a preferred route for routing the call to the call destination via the telecommunications system and credit data representative of remaining credit within an account limit of the subscription account;    initiating means for initiating communication with the call destination using the routing data; and credit control means for controlling the duration of the communication in accordance with the credit data.    
   
   
       2 . A device as claimed in  claim 1 , wherein the credit control means comprises means to prevent initiation of communication with the call destination if the credit data is representative of a minimum value credit remaining in the account.  
   
   
       3 . A device as claimed in any preceding  claim 1  wherein the credit data is representative of a maximum call duration corresponding to the remaining credit in the account and wherein the device comprises terminating means for terminating the communication with the call destination when the maximum call duration has elapsed.  
   
   
       4 . A device as claimed in  claim 3 , wherein the terminating means comprises means for calculating an elapsed time measured from the start of communication with the call destination as indicated by a clock of the device and determining means for determining when the elapsed time reaches the maximum call duration.  
   
   
       5 . A device as claimed in  claim 3 , wherein the credit data comprises a value representing a number of units determined by the control centre, the terminating means comprising means for measuring a time interval corresponding to one unit and counter means for counting said intervals from the start of communication with the call destination and determining means for determining when the number of intervals equals the number of units.  
   
   
       6 . A device as claimed in any preceding  claim 1 , wherein the input data comprises a telephone number of the call destination, wherein the routing data is representative of at least part of a preferred telephone number defining the preferred route, and wherein the initiating means is operable to initiate communication using the preferred telephone number.  
   
   
       7 . A device as claimed in  claim 6  wherein the routing data is representative of the entire preferred telephone number for use by the initiating means.  
   
   
       8 . A device as claimed in  claim 6  wherein the routing data is representative of a prefix code and wherein the initiating means comprises means for adding the prefix code to the input telephone number to obtain the preferred telephone number.  
   
   
       9 . A device as claimed in  claim 1  wherein the response message comprises protocol information and wherein the initiating means is responsive to the protocol information when initiating communication with the call destination using the routing data.  
   
   
       10 . A device as claimed in  claim 9  wherein the protocol information defines a wait period to be inserted between outputting an initial portion and a remaining portion of the preferred telephone number.  
   
   
       11 . A device as claimed in  claim 1 , wherein the input data comprises a network address of the call destination.  
   
   
       12 . A device as claimed in  claim 1  comprising means for storing identification information for identifying the device in use to the control centre and wherein the message generating means is operable to include the identification information in the request message.  
   
   
       13 . A device as claimed in  claim 1  wherein the initiating means is operable to initiate communication in use with the control centre whereby the output means is operable to output the request message via the telecommunications system.  
   
   
       14 . A device as claimed in  claim 1  wherein the output means is operable to output the request message using a first communications channel which is separate and distinct from a second communications channel used by the initiating means.  
   
   
       15 . A device as claimed in  claim 14  wherein the first communications channel comprises one of: 
 (a) the Internet;    (b) a public data network; and    (c) a private data network.    
   
   
       16 . A device as claimed in  claim 1  wherein the device is constituted by a telecommunications terminal and wherein the input means comprises a keypad for the input of the input data by a user.  
   
   
       17 . A device as claimed in  claim 14  wherein the terminal comprises a mobile telephone for wireless communication in use with a mobile telephone network of the telecommunications system.  
   
   
       18 . A device as claimed in  claim 15  wherein the output means is operable to output the request message in a text message format corresponding to a text message protocol of the mobile telephone network.  
   
   
       19 . A device as claimed in  claim 17  wherein the receiving means is operable to receive the response message in a text message format corresponding to a text message protocol of the mobile telephone network and wherein the mobile telephone is operable to inhibit display to the user of text corresponding to the response message.  
   
   
       20 . A device as claimed in  claim 17  further comprising means for updating at least one of a preferred network table and a barred network table using updating information contained in the response message.  
   
   
       21 . A device as claimed in  claim 17 , wherein the credit control means comprises an application processed by a SIM card of the mobile telephone.  
   
   
       22 . A device as claimed in  claim 16  wherein the device is constituted by a telephone for land line communication.  
   
   
       23 . A device as claimed in  claim 16  comprising a facsimile machine.  
   
   
       24 . A device as claimed in  claim 16  comprising a computer apparatus having a modem.  
   
   
       25 . A device as claimed in  claim 1  wherein the device is constituted by an interface apparatus having means for connection to at least one user operable terminal, wherein the input means is operable to receive the input data via said connection means from the user operable terminal.  
   
   
       26 . A device as claimed in  claim 25  wherein the device is constituted by a routing device having means for connection to a user operable terminal and wherein the input means is operable to receive the input telephone number via the connection means.  
   
   
       27 . A device as claimed in  claim 22  further comprising an interface module for communicating with a local area network to which the control centre is connected in use.  
   
   
       28 . A device as claimed in  claim 1  wherein the subscription account is a prepaid subscription account and wherein the account data representative of remaining credit corresponds to call charges for which prepayment has been made.  
   
   
       29 . A method of operating a telecommunications device for communication with a call destination via a telecommunications system using a credit controlled subscription account, the method comprising the steps of; 
 receiving an input telephone number defining the call destination;    generating a request message comprising data representative of the input telephone number; outputting the request message to a control centre;    receiving a response message from the control centre, the response message comprising routing data defining a preferred route for routing the call to the call destination via the telecommunications system and credit data representative of remaining credit within an account limit of the subscription account;    initiating a telephone call connection to the call destination using the routing data; and controlling the duration of communication in accordance with the credit data.    
   
   
       30 . A method as claimed in  claim 29 , comprising preventing initiation of communication with the call destination if the credit data is representative of a minimum value credit remaining in the account.  
   
   
       31 . A method as claimed in  claim 29 , wherein the credit data is representative of a maximum call duration corresponding to the remaining credit in the account and wherein the method comprises the step of terminating the communication with the call destination when the maximum call duration has elapsed.  
   
   
       32 . A method as claimed in  claim 31 , wherein the terminating step comprises calculating an elapsed time measured from the start of communication with the call destination as indicated by a clock of the device and determining when the elapsed time reaches the maximum call duration.  
   
   
       33 . A method as claimed in  claim 31 , wherein the credit data comprises a value representing a number of units determined by the control centre, the terminating step comprising measuring a time interval corresponding to one unit and counting said intervals from the start of communication with the call destination and determining when the number of intervals equals the number of units.  
   
   
       34 . A method as claimed in  claim 29  wherein the input data comprises a telephone number of the call destination, wherein the routing data is representative of at least part of a modified telephone number defining the preferred route, and wherein the initiating step initiates communication using the modified telephone number.  
   
   
       35 . A method as claimed in  claim 34  wherein the routing data is representative of the entire preferred telephone number for use in the initiating step.  
   
   
       36 . A method as claimed in  claim 34  wherein the routing data is representative of a prefix code and wherein the initiating step comprises adding the prefix code to the input telephone number to obtain the preferred telephone number.  
   
   
       37 . A method as claimed in  claim 33  wherein the response message comprises protocol information and wherein the initiating step is made responsive to the protocol information when initiating communication with the call destination using the routing data.  
   
   
       38 . A method as claimed in  claim 37  wherein the protocol information defines a wait period to be inserted between outputting of an initial portion and a remaining portion of the modified telephone number.  
   
   
       39 . A method as claimed in  claim 33  wherein the input data comprises a network address of the call destination.  
   
   
       40 . A method as claimed in  claim 29  comprising storing identification information for identifying the device in use to the control centre and wherein the message generating step includes the identification information in the request message.  
   
   
       41 . A method as claimed in  claim 29  wherein the initiating step initiates communication with the control centre whereby the request message is output via the telecommunications system.  
   
   
       42 . A method as claimed in  claim 29  wherein the output step outputs the request message using a first communications channel which is separate and distinct from a second communications channel used in the initiating step.  
   
   
       43 . A method as claimed in  claim 42  wherein the request message is output via one of: 
 (a) the Internet;    (b) a public data network; and    (c) a private data network.    
   
   
       44 . A method as claimed in  claim 29  wherein the device is constituted by a telecommunications terminal and wherein the receiving step comprises receiving the input of the input data by a user via a keyboard.  
   
   
       45 . A method as claimed in  claim 29  wherein the terminal comprises a mobile telephone for wireless communication with a mobile telephone network of the telecommunications system.  
   
   
       46 . A method as claimed in  claim 45  wherein the request message is output in a text message format corresponding to a text message protocol of the mobile telephone network.  
   
   
       47 . A method as claimed in  claim 45  wherein the response message is received in a text message format corresponding to a text message protocol of the mobile telephone network and wherein the mobile telephone inhibits display to the user of text corresponding to the response message.  
   
   
       48 . A method as claimed in  claim 45  further comprising updating at least one of a preferred network table and a barred network table using updating information contained in the response message.  
   
   
       49 . A method as claimed in  claim 45 , wherein the control of duration in accordance with credit data comprises operating an application processed by a SIM card of the mobile telephone.  
   
   
       50 . A method as claimed in  claim 29 , wherein the device is constituted by an interface apparatus providing connection to at least one user operable terminal, wherein the receiving step comprises receiving the input data from the user operable terminal.  
   
   
       51 . A method as claimed in  claim 50  wherein the device is constituted by a routing device providing connection to a user operable terminal and wherein the receiving step comprises receiving the input telephone number via the connection with the user operable terminal.  
   
   
       52 . A method as claimed in  claim 29  wherein the subscription account is a prepaid subscription account and wherein the account data representative of remaining credit corresponds to call charges for which prepayment has been made.  
   
   
       53 . A control centre comprising; 
 receiving means operable to receive a request message comprising data representative of an input telephone number defining a call destination and information defining the location of a device from which communication with the call destination via a telecommunications system is required;    means for determining a preferred route for communication via the telecommunications system;    means for determining credit: data representative of remaining credit in a prepaid subscription account of a user of the device;    means for generating a response message comprising routing data representative of at least part of a preferred telephone number to be used by the device and comprising the credit data;    and means for transmitting the response message to the device.    
   
   
       54 . A method of operating a control centre comprising; 
 receiving a request message comprising data representative of an input telephone number defining a call destination and information defining the location of a device from which communication with the call destination via a telecommunications system is required;    determining a preferred route for communication via the telecommunications system;    generating a response message comprising routing data representative of at least part of a modified telephone number to be used by the device and credit data representative of remaining credit in a prepaid subscription account of a user of the device;    and transmitting the response message to the device.    
   
   
       55 . A computer program comprising processor implementable instructions for controlling a telecommunications device to carry out a method for communication with a call destination via a telecommunications system using a credit controlled subscription account, the method comprising the steps of: 
 receiving an input telephone number defining the call destination;    generating a request message comprising data representative of the input telephone number; outputting the request message to a control centre;    receiving a response message from the control centre, the response message comprising routing data defining a preferred route for routing the call to the call destination via the telecommunications system and credit data representative of remaining credit within an account limit of the subscription account; initiating a telephone call connection to the call destination using the routing data; and controlling the duration of communication in accordance with the credit data.    
   
   
       56 . A storage medium storing processor implementable instructions for controlling a telecommunications device to carry out a method for communication with a call destination via a telecommunications system using a credit controlled subscription account, the method comprising the steps of: 
 receiving an input telephone number defining the call destination;    generating a request message comprising data representative of the input telephone number; outputting the request message to a control centre;    receiving a response message from the control centre, the response message comprising routing data defining a preferred route for routing the call to the call destination via the telecommunications system and    credit data representative of remaining credit within an account limit of the subscription account;    initiating a telephone call connection to the call destination using the routing data; and controlling the duration of communication in accordance with the credit data.    
   
   
       57 . A signal carrying processor implementable instructions for controlling a telecommunications device to carry out a method for communication with a call destination via a telecommunications system using a credit controlled subscription account, the method comprising the steps of: 
 receiving an input telephone number defining the call destination;    generating a request message comprising data representative of the input telephone number; outputting the request message to a control centre;    receiving a response message from the control centre, the response message comprising routing data defining a preferred route for routing the call to the call destination via the telecommunications system and credit data representative of remaining credit within an account limit of the subscription account;    initiating a telephone call connection to the call destination using the routing data; and controlling the duration of communication in accordance with the credit data.