XEP-0327: Rayo defines an XMPP protocol extension for the third-party control of telephone calls and other similar media sessions. The protocol includes support for session management/signaling, as well as advanced media resources such as speech recognizers, speech synthesizers and audio/video recorders. The protocol serves a different purpose from that of first-party protocols such as Jingle or SIP, and is compatible with those protocols.
Make sure Openfire is running on a Public IP interface and with Firewall opened for UDP Traffic both ways on port range 30000 to 50000.