Inter-Asterisk eXchange

"IAX" redirects here. For the airline with the ICAO code IAX, see Island Express Air. For the Type Iax supernova, see Type Iax supernova.
Inter-Asterisk eXchange
Communication protocol
AbbreviationIAX
PurposeVoIP
Developer(s)Mark Spencer
Introduction ()
InfluencedIAX2
OSI layerApplication layer
Port(s)4569
RFC(s)RFC 5456
Internet protocol suite
Application layer
Transport layer
Internet layer
Link layer

Inter-Asterisk eXchange (IAX) is a communications protocol native to the Asterisk private branch exchange (PBX) software, and is supported by a few other softswitches, PBX systems, and softphones. It is used for transporting voice over IP telephony sessions between servers and to terminal devices.

The original IAX protocol is deprecated and has been superseded by a second version, commonly called IAX2. The IAX2 protocol was published as an informational (non-standards-track) RFC 5456 by discretion of the RFC Editor in February 2010.[1]

  1. ^ RFC 5456, page 1: "Status of This Memo This memo provides information for the Internet community. It does not specify an Internet standard of any kind."