IAX DirectMedia

General Help
1

Hello,

Newbie here. Can someone please direct me on how to setup directmedia for IAX extensions. I have done it for SIP extensions using ‘directrtpsetup=yes’ and it worked right away. But what are the steps for IAX.

Thanks in advance.

2

There are no steps, you can’t do that, IAX2 is a monolithic protocol where everything is encapsulated in the same udp connection.

3

(IAX=InterAsteriskeXchange protocol, there is no concept of extra asterii)

4

Hello again,

I kind of suspected this, but, some guy posted this, and then really made me scratch my head. Please check out the 5th paragraph on the following link:
http://www.geekdom.net/blog/archives/2007/07/10/why_sip_sucks_and_iax_rocks_a_rant_on_latency_and_the_media_path.html

Thanks again

5

Your point being?

6

My point is that this guy implies that it is possible. Again I am new here. Just wanted to get the most accurate information. Thanks!

7

Then ask that guy. personally I don’t see that working but I have been wrong before.

8

That blog post is very odd, it is unclear.

First of all IAX used one port , UDP 4569 so signalling and bearer info is always in the same stream.

What I think the blog guys is talking about is an Asterisk feature that if you transfer a call with IAX to another IAX then the transferring machine can step out of the way. Unless you have rare chinese IAX phones and even rarer IAXY from Digium or a tandem switch in the middle of a bunch of other asterisk boxes don’t worry about it.

9

Hey, good to get your attention on that blog post. I use Zoiper, with IAX accounts. I am still a little confused as to the native transfer part. Is there any setting I need to activate on FreePBX or is this done on the softphone?

Thanks again and forgive my lack of knowledge on the subject.

10

… and, though I haven’t actively managed an Asterisk/freebpx/etc. install recently, I believe everyone else’s answers are correct. IAX is a monolithic protocol, but to get the media to flow directly between endpoints, you’d have to initiate a transfer. That post basically just says “look, IAX thought it all the way through, you can actually use this feature”. Or, at least, I think that’s what it says.

But, yeah, you’d need native-IAX endpoints to make it matter. And you just it just by doing a (“native”) transfer. I believe I used this a few times to speed up latency when I had an Internet-facing Asterisk and a behind-a-NAT residential Asterisk, to reduce the latency. When your using a west-coast VoIP termination service from the west coast, bouncing your media through Pennsylvania (where, ironically, I now live) meant adding latency. That darned speed of light. But doing a native transfer meant that you could keep the ingress rules/etc. on the Internet facing box, but bounce the media to the behind-the-firewall Asterisk to get the latency back down, without the nightmare of making sure all of the VoIP devices knew how to route their media correctly from behind the NAT.