First of all, the Applet-phone is a SIP User-Agent

with audio and text messaging capabilities. But i s also embedded in

an applet where you can use it as usual if your firewall allow you to

use the UDP transport. If not, you can use TCP to carry your voice in a

voice messaging fashion. Your voice is recorded and encoded locally

then sent as a message, decoded and played back by your peer. Voice

messaging allow you to go through any firewall, so that you can

continue to chat and talk with your friends from an applet !