Re: [MMUSIC] T.38 (Re: M-line philosophy (Re: Wisdom sought: Prioritization of codecs))

"Schwarz, Albrecht (Albrecht)" <albrecht.schwarz@alcatel-lucent.com> Thu, 22 November 2012 14:13 UTC

Return-Path: <albrecht.schwarz@alcatel-lucent.com>
X-Original-To: mmusic@ietfa.amsl.com
Delivered-To: mmusic@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 8A51321F895E for <mmusic@ietfa.amsl.com>; Thu, 22 Nov 2012 06:13:35 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.098
X-Spam-Level:
X-Spam-Status: No, score=-9.098 tagged_above=-999 required=5 tests=[AWL=-1.149, BAYES_00=-2.599, HELO_EQ_FR=0.35, MANGLED_OFF=2.3, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id PzJu8RG9y1hN for <mmusic@ietfa.amsl.com>; Thu, 22 Nov 2012 06:13:34 -0800 (PST)
Received: from smail2.alcatel.fr (smail2.alcatel.fr [64.208.49.57]) by ietfa.amsl.com (Postfix) with ESMTP id A1BE421F847F for <mmusic@ietf.org>; Thu, 22 Nov 2012 06:13:34 -0800 (PST)
Received: from FRMRSSXCHHUB04.dc-m.alcatel-lucent.com (FRMRSSXCHHUB04.dc-m.alcatel-lucent.com [135.120.45.64]) by smail2.alcatel.fr (8.14.3/8.14.3/ICT) with ESMTP id qAME05qZ007001 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NOT) for <mmusic@ietf.org>; Thu, 22 Nov 2012 15:00:12 +0100
Received: from FRMRSSXCHMBSD2.dc-m.alcatel-lucent.com ([135.120.45.50]) by FRMRSSXCHHUB04.dc-m.alcatel-lucent.com ([135.120.45.64]) with mapi; Thu, 22 Nov 2012 14:59:43 +0100
From: "Schwarz, Albrecht (Albrecht)" <albrecht.schwarz@alcatel-lucent.com>
To: "mmusic@ietf.org" <mmusic@ietf.org>
Date: Thu, 22 Nov 2012 14:59:42 +0100
Thread-Topic: [MMUSIC] T.38 (Re: M-line philosophy (Re: Wisdom sought: Prioritization of codecs))
Thread-Index: Ac3Itsv14bj2MiQoQIivv6tR4UFhowAAN0Ng
Message-ID: <5F7BCCF5541B7444830A2288ABBEBC9623DF0C4376@FRMRSSXCHMBSD2.dc-m.alcatel-lucent.com>
References: <50AE2838.9000807@ericsson.com> <50AE2B02.2020900@ericsson.com>
In-Reply-To: <50AE2B02.2020900@ericsson.com>
Accept-Language: de-DE, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: de-DE, en-US
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-Scanned-By: MIMEDefang 2.69 on 155.132.188.80
Subject: Re: [MMUSIC] T.38 (Re: M-line philosophy (Re: Wisdom sought: Prioritization of codecs))
X-BeenThere: mmusic@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Multiparty Multimedia Session Control Working Group <mmusic.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mmusic>, <mailto:mmusic-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mmusic>
List-Post: <mailto:mmusic@ietf.org>
List-Help: <mailto:mmusic-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mmusic>, <mailto:mmusic-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 22 Nov 2012 14:13:35 -0000

Looks like that your are describing T.37 FoIP behaviour, whereas Adam did point on T.38 FoIP.

WebRTC should firstly agree
a) whether fax is part of this conversational realtime multimedia service at all,
and if,
b) which transport mode via IP.

To a): support of F.185 (Internet fax) Yes/No
To b): 
	b.1) T.37 FoIP store-and-forward already sufficient Yes/No
	b.2) T.38 FoIP realtime required Yes/No ((perhaps T.38 over RTP/UDP or UDPTL/UDP))
	b.3) or any alternative to T.38 FoIP realtime Yes/No

NOTE: T.38 would specify the behaviour of the 
1) PSTN gateway (as "T.38 gateway", which is always a PSTN-to-IP gateway) and
2) Browser (as "T.38 IAD" (Internet aware fax device))
in below illustration.

-Albrecht

-----Original Message-----
From: mmusic-bounces@ietf.org [mailto:mmusic-bounces@ietf.org] On Behalf Of Stefan Hakansson LK
Sent: Donnerstag, 22. November 2012 14:39
To: mmusic@ietf.org
Subject: Re: [MMUSIC] T.38 (Re: M-line philosophy (Re: Wisdom sought: Prioritization of codecs))

On 11/20/2012 15:56, Adam Roach wrote:
>
>
>    +---------+   +------------+   +---------+
>    | Web App |---| SIP Server |---|         |
>    +---------+   +------------+   |         | +-------------+
>         |                         | PSTN GW |--| Fax Machine |
>    +---------+      media         |         | +-------------+
>    | Browser |--------------------|         |
>    +---------+                    +---------+

For cases when one client is not a proper fax machine, is not the usual 
thing that is done that the facsimile is converted to/from TIFF, JPEG, 
PDF or similar somewhere between that client and the fax machine? (And 
often sent as a mail attachment)

If so, all tools are already available (e.g. File API if you want to 
store/access on the local file system, XHR or WebSockets - or even the 
rtcweb data channel for transport) to build a client that can handle 
fax. (I am probably missing something)

Stefan

_______________________________________________
mmusic mailing list
mmusic@ietf.org
https://www.ietf.org/mailman/listinfo/mmusic