IAX Trunk and SIP Devices

Does that work? I haven’t tried it out, but I noticed that Voip.ms has an IAX trunk. I have read online that IAX will perform a bit better than SIP under most conditions. Would the FreePBX machine have to convert between the two, or is that just a header change?

Either way, any comments on using IAX2/SIP for trunk/devices vs SIP/SIP trunk/devices?

Yes, an IAX Trunk will work. I don’t believe that any transcoding is needed. I think the only difference is the protocal used to establish the calls. The major advantage to IAX is that you can avoid the bug that causes Asterisk to completely crash when you lose internet access. The only downside is that very few providers support IAX. But, VOIP.ms does, so there you go…

Transcoding only involves media, so if you have the devices using the same CODEC. SIP trunks have the same issue.

The advantage if IAX is it works with NAT flawlessly, media and signalling use a single port and multiple calls can travel in the same tunnel.

We use IAX exclusively for trunking and I am a huge fan of the protocol.

Good to hear. I’ll switch to using that and see what happens.