It seems to be hit and miss, certainly not 100%, but better than trying to use either PCMU or PCMA over the commodity Internet for FAXing. PCMU/PCMA might work over a local private LAN with QoS enabled and the jitter down to almost nothing. The biggest issue I've seen with T38 is the ATA's inability to properly negotiate a Super-G3 fax down to G3 or slower speeds. In our experience, you need to disable the Super-G3 feature of the FAX machine to slow it down to either 14.4 or 9600 and disable ECM. Many of the newer FAX machines have a "VoIP Compatibility" mode which essentially slows it down to 9600 and disables ECM. We predominantly use Cisco/Linksys/Sipura ATAs, but would like to hear if anyone has better experiences with other ATAs, particularly in business environments where there's potentially a lot of FAXing. Cheers, Gabe On Wed, Jan 6, 2010 at 6:00 PM, Ujjval Karihaloo <ujjval at simplesignal.com> wrote:
I know this a thorn in everyones flesh, I would like to know of experiences with T38 Voip Faxing. We have had good and bad. Those that don?t work just don?t and they don?t even want to troubleshoot and just switch over to an Analog line for Fax. We mostly use AudioCodes and Sipura T38 ATAs.
Any of you folks do T38 and whats the experience like.
_______________________________________________ VoiceOps mailing list VoiceOps at voiceops.org https://puck.nether.net/mailman/listinfo/voiceops