On Fri, Apr 29, 2016 at 1:34 AM, Olivier <[email protected]> wrote: > Hello, > > I'm helping a colleague (*) which has the following setup: > > ITSP --- <T.38 capable PJSIP trunk> --- Asterisk 13 --- <PJSIP>-- > Audiocodes MP-112 --- <FXO/FXS> --- Fax machine > > My issue is the following : > Audiocodes gateway reject INVITEs with 488 Not Acceptable Here > > It seems this gateway requires t38 settings to be present in SDP body in the > very first INVITE. > > My questions are the following: > > 1. I expected T.38 to exclusively work with reINVITE where calls are > established as normal voice calls (PCMA/PCMU in SDP, for instance) and then > upgraded to T.38 (when CNG is detected, for instance). > Have you ever heard of T.38 sessions being established right from the start > (ie with T.38 settings in the first INVITE) ?
No. It would seem to be extremely broken if it denies a call based on a lack of T.38 sdp parameters on the initial INVITE. > 2. Is it possible to configure Asterisk to pass T.38 settings in SDP in the > first INVITE it sends ? > > 3. Any suggestion with Audiocodes gateway ? Look for T.38 settings maybe? See if there is something keeping you from sending an initial invite with non-T.38 SDP....? -- Matthew Fredrickson Digium, Inc. | Engineering Manager 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
