> This depends on the path. If it is > > FAX machine A -> gateway A-> gateway B -> FAX machine B > > something like the following will happen. FAX machine A calls, and the > call reaches FAX machine B with an audio path. FAX machine B sends the > answer tone, which gateway B hears. Gateway B mutes the audio path while > it attempts T.38 negotiation. Gateway B and gateway A chat, and switch > into T.38 mode. Gateway B might then send the "answer tone present" > signal to gateway A, or it may not. They are pretty sloppy about this. > Now things should be running in T.38 mode, but probably the only answer > tone that arrived at FAX machine A was the first 20 or 30 ms. > > FAX machine A should hear bursts of V.21 every few seconds, so there > should be no ambiguity about having reached FAX machine B.
Thanks Steve. I have just discovered that if I call from a normal PSTN phone, I get a tax tone every time. If I call from a VoIP phone, hardly ever get a fax tone, just silence. _______________________________________________ Callweaver-users mailing list [email protected] http://lists.callweaver.org/mailman/listinfo/callweaver-users
