A method of establishing a collaborative domain among a plurality of communication terminals can include having a communication terminal authenticate one or more other communication terminals based on personal information, which can be stored on a removable memory card in the other terminals, and/or based on the geographic location of the other terminals. A first communication terminal can determine the geographic location of a second communication terminal and can authenticate the second communication terminal in response to both the determined geographic location and personal information defined in the second communication terminal. In response to the authentication by the first communication terminal, communication of user and/or program information, which is unrelated to authentication, is allowed between at least the first and second communication terminals.