Advanced → IAX sets the global options of IAX2, the Inter-Asterisk eXchange protocol. IAX is used by some providers and for linking Asterisk systems; it carries signalling and audio over a single UDP port, which makes it easy to pass through NAT. Phones and providers that use IAX are set up under Accounts like SIP ones.
Click Save and then apply the changes, see Applying changes.
Settings
| Field | Meaning | Default |
|---|---|---|
| Accept IAX connections (firewall) | Open the IAX port in the firewall. Turn it off when you use no IAX phones or providers. Only the firewall rule changes; outgoing IAX connections, for example a registration at a provider, continue to work. | on |
| IAX port | UDP port for IAX, 1–65535. | 4569 |
| Enable jitter buffer | Smooth out uneven packet arrival on IAX calls, at the cost of a little delay. | off |
| Force jitter buffer | Use the jitter buffer even when the other side of the call could handle the jitter itself. | off |
| Additional [general] options | key=value lines appended to the [general] section of iax.conf, for experts. | empty |
If Advanced → Firewall restricts the networks allowed to use SIP/IAX, that restriction applies to the IAX port as well.