The invention relates to a method for authorizing a telephone transaction and in particular an access to a database through a user in a telecommunication network, said telecommunication network comprising a user interface, an access control for the database and an authentification device, which are connected with each other over a local node in the telecommunication network, as well as to a corresponding local node.The invention is characterized in that the comparative result is output by the authentification device over the local node to the access control and the result of the comparison is communicated by the access control to the user over the local node, signals sent by the authentification device being masked.