US Patent 8259920 Call extension in telecommunications systems

A method is disclosed that enables a user of one telecommunications terminal that is engaged in a call to move or “extend” the call to a second telecommunications terminal without notifying any other party on the call of the move. This is particularly useful in many situations. For example, the user might be at work and engaged in a call with a client on the user's wireline desk telephone. If the user needs to leave the office, the user can extend the call to his or her cell phone, while the call is in progress, without notifying the client. This enables the user to leave the office and continue the call on his or her cell phone without having the client ever know that the user is on his or her cell phone and not in the office.