We seem to be having a good bit of issues sending faxes and can't pinpoint the issue. I'm hoping someone here may have a different outlook on the issue that leads to a resolution. Our call path is Sip trunk from MAX TNT - Asterisk - T1 - Adtran endpoint converting sip trunk to copper line for house wiring. Users at the endpoint can receive faxes without a problem. However, sending faxes are not so friendly. 1 out of 5 faxes will send successfully. The remaing 4 continually fail with the fax machines reporting "Poor Line Quality". QoS is setup on both ends and working as expected across all traffic to and from both sides of the call. Voice quality is good on calls from the same lines. I've checked all sides and had all vendors look at their equipment and they are all pointing the finger at each other. I've got sip traces from both ends and both look good with the exception of random BYE's being sent from the Adtran side of the call during random fax calls. T.38 is enabled on both ends as well. Anyone have any possible ideas where to look further or an idea of how i could at least improve the situation? Thanks. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.digium.com/pipermail/asterisk-users/attachments/20090522/2097875f/attachment.htm
Todd S wrote:> Our call path is Sip trunk from MAX TNT - Asterisk - T1 - Adtran > endpoint converting sip trunk to copper line for house wiring. > > Users at the endpoint can receive faxes without a problem. However, > sending faxes are not so friendly. 1 out of 5 faxes will send > successfully. The remaing 4 continually fail with the fax machines > reporting "Poor Line Quality". QoS is setup on both ends and working > as expected across all traffic to and from both sides of the call. > Voice quality is good on calls from the same lines. I've checked all > sides and had all vendors look at their equipment and they are all > pointing the finger at each other. I've got sip traces from both ends > and both look good with the exception of random BYE's being sent from > the Adtran side of the call during random fax calls. T.38 is enabled > on both ends as well. > > Anyone have any possible ideas where to look further or an idea of how > i could at least improve the situation?Is T.38 actually being used? If not, then please see: http://hylafax.sourceforge.net/docs/fax-over-voip.pdf If T.38 is being used then it's probably due to a T.38 bug in one or more of the gateways, and you'll need to work with the provider of that T.38 gateway for a resolution. Thanks, Lee.