The loopback mike button will cause input from the mike to be sent to the local speaker/jack. This might be useful for checking levels and debugging cable problems but the delay from input to output makes talking in this mode almost impossible. The three tone buttons will generate one of three reference tones through the local speaker. Level setting should generally be done with the -6dBm tone.
Conference mode This is the default when vat starts up unless the command-line flag (-l) is set on invocation. vat attempts to minimize the delay since large delays make interactive conversations difficult. This usually results in more lost packets when the delay becomes too short handle congestion.
Lecture mode In this mode, vat attempts to minimize lost packets by reducing delays very slowly. This results in the clearest playback but interactivity may suffer.
Port The port number of the conference. Set at time of invocation.
TTL This is the parameter set at invocation which determines the scope of the conference. It is VERY important to set this to an appropriate level for your conference. A full discussion of etiquette for use of the Mbone is given in the Guide to Multi-media Conferencing.
Name may be changed to announce a new session name to other participants.
Key can be used to specify an encryption key, if required to gain privacy. vat allows the audio packet streams to be DES encrypted. Details of this facility are given in the vat manual page.
Title may be entered to rename the main window.