IAX2 – Inter-Asterisk eXchange

IAX2 (Inter-Asterisk eXchange protocol) is the new kid on the block; born from the open source Asterisk PBX. The author (Mark Spencer) saw the drawbacks in SIP (primarily problems with traversing firewalls and NAT) and created a the new protocol. IAX2 has its main advantage in being simple; this enables it to traverse firewalls and NAT, and it also keeps bandwidth requirements to a minimum. It is growing in popularity along with the associated Asterisk PBX.

Form more information on IAX2 use the following links:

• Draft protocol description

• Asterisk PBX