Agreed. The key really is g.711 (usually u-law) and low (read no) latency/jitter unless you can fully interop T.38 across the network. Most fax machines will auto-negotiate to the lower speeds when needed, but low to middle end Brother machines may be a major exception as they often have a poor T.30 implementation. -Scott From: voiceops-bounces at voiceops.org [mailto:voiceops-bounces at voiceops.org] On Behalf Of Kenny Sallee Sent: Friday, August 28, 2009 12:06 PM To: voiceops at voiceops.org Subject: [VoiceOps] FAX over VOIP networks So the last thread on T38 made me want to start a thread on FAX over IP via an ATA or something like the Adtran TA900 series.
From our experience, to be most successful w/ FAX over IP of any sort we've found that if you:
1.) Set baud to lowest setting fax can handle 2.) Lower print quality settings if possible 3.) Make sure to force G711 4.) Disable ECM and VAD on fax/modem tone detection And then cross your fingers fax's are successful and consistent. Anyone else have other experiences or suggestions? Kenny