SIP using IAX link?

[gandalf]

Does anyone know of teleco’s offering SIP trunks via a IAX link? It occurs to me that one might use a trixbox to front end a sip solution on any phone system. SIP trunks on ShoreTel, for example, are a nightmare! All the firewall stuff! If you could front end the ShoreTel with a SIP tie line to a trixbox that is providing IAX connectivity to a sip dial tone provider I think that would be hot! Any thoughts!

[lindlyrawlins]

Some providers (such as VoicePulse) offer IAX2 trunks. Keep in mind that SIP and IAX2 are completely separate protocols…there isn’t such a thing as a SIP trunk over IAX.

And yes…both SIP and IAX2 have their pros and cons. SIP requires way too many UDP ports to be opened in the firewall, but can handle much higher call volumes because of that. IAX2 only requires one port to be open, but because of that, connection information and voice traffic are handled on the same port which causes the OS to use additional file handles…so now your call volume is limited by the hardware of the server.

If you are looking for a good IAX2 service provider…try VoicePulse…they are very simple to configure and use.

IAX2 provider ? IAX2 trunk ? Firewall (port 4569) ? trixbox ? SIP trunk ? ShoreTel. That should work.