1.5 Administrator's Guide

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  3. 1.5 Administrator’s Guide
  4. Commissioning the unit
  5. Trunk groups and VOIP providers
  6. Inter-Asterisk Exchange (IAX) trunks
  7. Adding an IAX trunk

Adding an IAX trunk

To add an IAX provider, activate the Add menu on the Trunks panel. Select IAX Provider.

IAX trunk configuration is divided into basic, advanced and codec configuration, accessible from their accompanying tabs on the IAX Provider form.




The unique name of this IAX trunk. If this trunk is an IAX provider, the name of the trunk must match the username.


A custom description of this IAX trunk


The address of the IAX provider’s registration server


The registration user name provided in the registration string to the IAX provider when registering. When registering, the username must be the same as the username configured in the IAX provider.


The registration password required by the IAX provider

Act as Provider

When enabled, this trunk allows other IAX users to register with it. An UNKNOWN peer will be created and the IP address of the peer associated with this trunk on registration.

Note: When configuring a Com.X to Com.X IAX trunk, if the registering trunk is configured and applied on the registering Com.X before the IAX provider configuration is applied on the Provider Com.X, the registering box will need a ‘iax2 reload’ to initiate registration. We therefore recommend configuring and applying the provider trunk before the registering trunk.

Register with Provider

When enabled, the IAX trunk will attempt to register its IP address with the IAX host at the provider address configured. The registration string will use the configured username.



Qualify connection

When enabled, checks the reachability of the peer every 60 seconds.

Contact # for incoming

A DID number to assign to incoming calls on this IAX trunk. This facilitates inbound routing where the DID is not provided by the IAX provider.

Maximum # channels

The maximum number of simultaneous IAX channels supported on this trunk. Leave blank for no limit.

Codecs supported by an IAX trunk can be selected by using the Codecs button. Use Ctrl-Left-Click (holding Ctrl down) to select multiple codecs. Individual codecs can be moved up and down the codec priority list by selecting the codec entry, and selecting the Up or Down buttons.

When negotiating an IAX call, the codec with the highest priority (at the top of the list) will be attempted first, then the second and so on. Codecs may specify the integration time in milliseconds after the codec name in the form codec:integration time, e.g. ‘g729:40’