A method of authenticating an authorized entity via the telephone network is disclosed. A telephone call is placed from a telecommunications terminal to a server that comprises a valuable resource and that only provides the resource to authorized entities. When the terminal has already demonstrated its authorization to the server, the server indicates to the terminal that the terminal need not provide its authorization credentials. In contrast, when the terminal has not yet demonstrated its authorization to the server, the server indicates to the terminal that the terminal does need to provide its authorization credentials. The server indicates to the terminal whether or not it needs to provide its authorization credentials by deliberating waiting to establish the call with the terminal, wherein in the length of the wait is indicative of whether or not the terminal needs to provide its authorization credentials.