System and method for limiting incoming spam calls

A method of controlling calls received by a telephone connected to a telephone network, comprising:

• determining whether to send a current incoming call from a phone number a current challenge prior to connecting the current incoming call to the telephone based on information related to the phone number including one or more of the following:
• a) a property of a calling number identification associated with the phone number;
• b) the presence of the phone number on a white list, a grey list or a blocked caller list;
• c) stored information indicating whether a previous incoming call from the phone number to the telephone passed a previous challenge;
• or d) stored information including the frequency and the recentness of previous calls from the phone number;
• sending a current challenge to the phone number, the current challenge comprising a request for a user associated with the current incoming call to press a randomly-selected digit or digits and in which the current challenge is passed if the requested randomly-selected digit or digits is pressed;
• and
• allowing the current incoming call to connect to the telephone if the current challenge is passed.

A system for controlling calls to a telephone on a telephone network, comprising:

• a network exchange configured to receive a current incoming call from the telephone network;
• and
• a call control processor configured to receive information relating to the current incoming call from the network exchange, the processor further configured to:
• determine whether to send the current incoming call from a phone number a current challenge prior to connecting the current incoming call to the telephone based on information related to the phone number including one or more of the following:
• a) a property of a calling number identification associated with the phone number;
• b) the presence of the phone number on a white list, a grey list or a black list;
• c) stored information indicating whether a previous incoming call from the phone number to the telephone passed a previous challenge;
• or d) stored information including the frequency and the recentness of previous calls from the phone number;
• send a current challenge to the phone number, the current challenge comprising a request for a user associated with the current incoming call to press a randomly-selected digit or digits and in which the current challenge is passed if the requested randomly-selected digit or digits is pressed;
• and
• allow the current incoming call to connect to the telephone if the current challenge is passed.

A call control unit for controlling calls received on a telephone network, comprising:

• a processor configured to receive information relating to a current incoming call associated with a phone number received by the telephone network, the current incoming call requesting a connection be made to a telephone on the telephone network;
• a server configured to store information related to the phone number including one or more of the following:
• a) a property of a calling number identification associated with the phone number;
• b) the presence of the phone number on a white list, a grey list or a black list;
• c) stored information indicating whether a previous incoming call from the phone number to the telephone passed a previous challenge;
• or d) stored information including the frequency and the recentness with previous calls from the phone number;
• and
• the processor being configured to:
• determine whether to send a current incoming call from a phone number a current challenge prior to connecting the current incoming call to the telephone based on the information stored on the server related to the phone number;
• send a current challenge to the phone number, the current challenge comprising a request for a user associated with the phone number to press a randomly-selected digit or digits and in which the current challenge is passed if the requested randomly-selected digit or digits is pressed;
• and
• allow the current incoming call to connect to the telephone if the current challenge is passed.