Description:

Inter Asterisk eXchange, lovingly called IAX (pronounced: eeks), is
the protocol used by the Asterisk PBX system for
inter-asterisk-communication. Other applications may use libiax to
communicate with each other and other asterisk servers. IAX is a high
performance, feature rich protocol unrelated to SIP or H.323. Its
single-socket design allows it to interoperate with NAT and PAT
masquerade firewalls. It supports internationalization, remote
dialplans, and voice, HTML, image, DTMF, and video content. For more
information see http://www.gnophone.com/.