This question comes up on a regular basis. The answer is "maybe". Some providers allow it, some don't.
See this thread
for some information. If your provider isn't mentioned there, do a forum search on "FAX" and you may turn up a thread where your provider is discussed.
Feedback received on this FAQ entry:
- Many of the VoIP provider's termination providers are premium and generally will support faxing over G.711 . Your biggest problem is going to be with your ISP. The problem seems to be they're overselling their networks to the point where QoS can be quite bad, even through your throughput may be OK. Do not disable ECM mode or reduce the baud rate below 14400, as many seem to suggest - it only makes things worse. Also you want echo cancellation ON.
2010-12-07 02:17:39 (jason_m )
- Callcentric with G.711 codec fax fine with our testing.