[SIPForum-discussion] FAX T.38

[mahdi salah]

No, that's not possible for now :( Enabling the T38 at A party will induce
to offering it in the SDP of the initial INVITE.

Mahdi

On Tue, Jan 22, 2013 at 9:46 PM, Sebastien BOIRE-LAVIGNE <
Sebastien.Boire-Lavigne at sagemcom.com> wrote:

> Yeah offering both G.711 and T.38 can confuse the B-party. I don’t see
> why, but it would not be a first since T.38 call flows are not always
> bullet proof. Can you enable T.38 on the A-Party without advertising it in
> the initial invite an just offer G.711?****
>
> *SBL***
>
> ** **
>
> *From:* discussion-bounces at sipforum.org [mailto:
> discussion-bounces at sipforum.org] *On Behalf Of *mahdi salah
> *Sent:* Tuesday, January 22, 2013 4:05 AM
> *To:* Sebastien BOIRE-LAVIGNE
> *Cc:* discussion at sipforum.org
>
> *Subject:* Re: [SIPForum-discussion] FAX T.38****
>
> ** **
>
> In fact, a first test was done without the support of T38 at A party side,
> so the INVITE is sent with only G711, then the audio RTP media link is
> correctly established and the re-INVITE for T.38 is successfully initiated
> by B Party, but the call is failed because A party does not support T.38.*
> ***
>
> Then we activated the support of T.38 at A party, and so the INVITE is
> sent including both Codecs G711 first and T.38 second. Also for this case
> the audio RTP media link is established correctly but there was no
> re-INVITE initiated by B Pa rty, and the Fax is successfully sent with G711.
> ****
>
> ** **
>
> So it seems like when there is T.38 in the first invite, B party won't
> initiate a re-INVITE.****
>
> ** **
>
> Equipments:****
>
> ** **
>
> A party : Huawei MGCF****
>
> B party : Alcatel Lucent MGCF   ****
>
> ** **
>
> Thanks****
>
> ** **
>
> On Mon, Jan 21, 2013 at 11:16 PM, Sebastien BOIRE-LAVIGNE <
> Sebastien.Boire-Lavigne at sagemcom.com> wrote:****
>
> Unless you can figure out the reason why the B-party doesn’t make the
> switch, you have little choice but to initiate the re-invite yourself.
>  Putting a muted T38 media is unlikely to  improve much, if the B-party is
> not even supporting the “basic” call flows. But it is trial and error at
> this point.****
>
>  ****
>
> Do you know the type of hardware/software of the B-party?****
>
> *SBL*****
>
>  ****
>
> *From:* discussion-bounces at sipforum.org [mailto:
> discussion-bounces at sipforum.org] *On Behalf Of *mahdi salah
> *Sent:* Monday, January 21, 2013 10:20 AM
> *To:* discussion at sipforum.org; Yee-KuangMoh****
>
>
> *Subject:* Re: [SIPForum-discussion] FAX T.38****
>
>  ****
>
>  ****
>
> Dear All,****
>
>  ****
>
> I am facing a problem with initiating the re-INVITE for T.38 by the B
> party.****
>
> The A party INVITE is sent including both media G711A and T.38 and then an
> RTP media link (G711) is correctly established for audio,****
>
> But there is no re-INVITE for T.38 sent by the B Party.****
>
>  ****
>
> What should be the problem? ****
>
> Is putting the T38 media to inactive in the first INVITE a solution ?****
>
>  ****
>
> Thanks****
>
> Mahdi****
>
> #****
>
> " Ce courriel et les documents qui lui sont joints peuvent contenir des****
>
> informations confidentielles ou ayant un caractère privé. S'ils ne vous sont****
>
> pas destinés, nous vous signalons qu'il est strictement interdit de les****
>
> divulguer, de les reproduire ou d'en utiliser de quelque manière que ce****
>
> soit le contenu. Si ce message vous a été transmis par erreur, merci d'en****
>
> informer l'expéditeur et de supprimer immédiatement de votre système****
>
> informatique ce courriel ainsi que tous les documents qui y sont attachés."****
>
>  ****
>
>  ****
>
>                                **********
>
>  ****
>
> " This e-mail and any attached documents may contain confidential or****
>
> proprietary information. If you are not the intended recipient, you are****
>
> notified that any dissemination, copying of this e-mail and any attachments****
>
> thereto or use of
>  their contents by any means whatsoever is strictly****
>
> prohibited. If you have received this e-mail in error, please advise th****
>
>  e****
>
> sender immediately and delete this e-mail and all attached documents****
>
> from your computer system."****
>
> #****
>
> #****
>
> " Ce courriel et les documents qui lui sont joints peuvent contenir des****
>
> informations confidentielles ou ayant un caractère privé. S'ils ne vous sont****
>
> pas destinés, nous vous signalons qu'il est strictement interdit de les****
>
> divulguer, de les reproduire ou d'en utiliser de quelque manière que ce****
>
> soit le contenu. Si ce message vous a été transmis par erreur, merci d'en****
>
> informer l'expéditeur et de supprimer immédiatement de votre système****
>
> informatique ce
>   courriel ainsi que tous les documents qui y sont attachés."****
>
> ** **
>
> ** **
>
>                                **********
>
> ** **
>
> " This e-mail and any attached documents may contain confidential or****
>
> proprietary information. If you are not the intended recipient, you are****
>
> notified that any dissemination, copying of this e-mail and any attachments****
>
> thereto or use of their contents by any means whatsoever is strictly****
>
> prohibited. If you have received this e-mail in error, please advise the****
>
> sender immediately and delete this e-mail and all attached documents****
>
> from your computer system."****
>
> #****
>
> ** **
>
> #****
>
> " Ce courriel et les documents
>  qui lui sont joints peuvent contenir des****
>
> informations confidentielles ou ayant un caractère privé. S'ils ne vous sont****
>
> pas destinés, nous vous signalons qu'il est strictement interdit de les****
>
> divulguer, de les reproduire ou d'en utiliser de quelque manière que ce****
>
> soit le contenu. Si ce message vous a été transmis par erreur, merci d'en****
>
> informer l'expéditeur et de supprimer immédiatement de votre système****
>
> informatique ce courriel ainsi que tous les documents qui y sont attachés."****
>
> ** **
>
> ** **
>
>                                **********
>
> ** **
>
> " This e-mail and any attached documents may contain confidential or****
>
> proprietary information. If you are not the intended recipient, you are****
>
> notified that any dissemi
>  nation, copying of this e-mail and any attachments****
>
> thereto or use of their contents by any means whatsoever is strictly****
>
> prohibited. If you have received this e-mail in error, please advise the****
>
> sender immediately and delete this e-mail and all attached documents****
>
> from your computer system."****
>
> #****
>
> #
> " Ce courriel et les documents qui lui sont joints peuvent contenir des
> informations confidentielles ou ayant un caractère privé. S'ils ne vous sont
> pas destinés, nous vous signalons qu'il est strictement interdit de les
> divulguer, de les reproduire ou d'en utiliser de quelque manière que ce
> soit le contenu. Si ce message vous a été transmis par erreur, merci d'en
> informer l'expéditeur et de supprimer immédiatement de votre système
> informatique ce courriel ainsi que tous les documents qui y sont attachés."
>
>
>                                ******
>
> " This e-mail and any attached documents may contain confidential or
> proprietary information. If you are not the intended recipient, you are
> notified that any dissemination, copying of this e-mail and any attachments
> thereto or use of their contents by any means whatsoever is strictly
> prohibited. If you have received this e-mail in error, please advise the
> sender immediately and delete this e-mail and all attached documents
> from your computer system."
> #
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20130122/ff886405/attachment-0002.html>