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.