Greger V. Teigre writes:
I suspect this is one of those questions where you know the answer ;-) Yes, you're of course right. You inject a direction=active in the failure_route, so that the GW will wait for the media before sending. However, I have had some issues with some clients that I haven't really figured completely out yet and I'm trying to be conservative. Do you have experiences where this work? If so, which GWs and clients do you have good experiences with?
in my configuration, i have always used pstn gw both directions without mediaproxy. proxy just adds direction=active to sdp towards gw if sip ua sis behind nat. i didn't know that there may be some issues. my gws are ciscos and i have had various sip uas such as grandstreams, cisco atas, sipuras, kphone, etc.
-- juha