We're on a large install of Adtran TA900s here, and we've had good successes with g711u with no T.38 option with low/no jitter, but are moving over to T.38. In the lab, at least, T.38 works great, once we divert our FoIP traffic to an Adtran end-point so that we can avoid our Cisco-Tekelec interoperability issues. -Owen Scott Berkman wrote:
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
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