fyi. Like also to recall that V.152 is for all kind of modem-based VBD services: a) fax/modem b) data/modem & c) text/modem. The correspondent packet relay techniques for VBDoIP are a) T.38 FoIP b) V.150.1 MoIP & c) V.151 ToIP. SDP for V.152 is described in V.152. SIP procedures for V.152, ditto. Further: any T.38 interoperability test needs to clarify also the used "T.38 version", which relates to the ITU-T release of T.38. There are in the meanwhile five (?) T.38 "variants" AFAIK: 1) T.38 1998 release (Ref.: ITU-T T.38 (06/98) 2) T.38 2002 release (Ref.: ITU-T T.38 (03/02) 3) T.38 2004 release (Ref.: ITU-T T.38 (04/04) 4) T.38 2005 release (Ref.: ITU-T T.38 (09/05) 5) T.38 2007 release (Ref.: ITU-T T.38 (04/07) The earlier releases missing e.g. the V.34 support. The later releases do also cover all the corrections and amendments made. Albrecht -----Original Message----- From: Eric Burger [mailto:eburger@xxxxxxxxxxxx] Sent: Dienstag, 4. November 2008 13:24 To: Schwarz Albrecht Subject: Re: V.152 Fax?; RE: First SIP Forum Fax Interoperability Workshop Can you take this issue to the techwg@xxxxxxxxxxxx list? Thanks. On Nov 4, 2008, at 3:23 AM, Schwarz Albrecht wrote: > Eric, > > any reasons why the fax transport option Fax-over-VBDoIP according > ITU-T > V.152 is out of scope of this workshop? > We do see much more deployments of V.152 vs T.38 in public VoIP NGNs. > And V.152 is also used in enterprise networks. > It's basically a matter of GoS of the IP transport network. > > V.152 offers non-assured and assured transport options. > > It should be also pointed out that there is a difference between "Fax > over G.711" and "Fax over V.152 with G.711 as VBD codec"! G.711 is > used as voice codec in the first option, and as VBD codec in the V.152 > mode. > The particular difference relates to the (G.168) EC handling and VBD > stimuli. > > The main benefits of V.152 fax vs T.38 fax are > a) significant less GW resources required in terms of DSP/CPU time & > memory ("cheaper") and > b) much simpler control/configuration parameters (thus, less inteop > issues). > > Furthermore: > there is an interoperability topic concerning the peering of T.38 and > V.152 IP domains. > There is a new standard in progress for that, see Draft ITU-T > V.IP2IP-VxF "V.152 to T.38 peering / interworking" > (http://www.itu.int/ITU-T/workprog/wp_search.aspx? > isn_sp=1&isn_sg=153), > because neither T.38 nor V.152 does scope the IP-to-IP scenario. > >> this is a *Fax* Interoperability Workshop. > > Should be: "this is a *T.38 Fax* Interoperability Workshop. :-) > > Also T.37 Fax is out of scope, right? > > BR, Albrecht > > > >> -----Original Message----- >> From: sipping-bounces@xxxxxxxx >> [mailto:sipping-bounces@xxxxxxxx] On Behalf Of Eric Burger >> Sent: Montag, 3. November 2008 20:34 >> To: sipping@xxxxxxxx >> Subject: First SIP Forum Fax Interoperability Workshop >> >> Yes, you read that right, this is a *Fax* Interoperability Workshop. >> >> >> Location: >> The W San Francisco Hotel -- (across the street from the Moscone >> Convention Center and the VoiceCon show) Workroom #2, 3rd Floor. >> 181 Third Street, San Francisco CA 94103 >> >> Date & Time: Monday, November 10, 2008 -- 11:00am - 3:00pm >> Cost: FREE >> Organizer: SIP Forum >> Lead Sponsor: Dialogic >> >> >> BACKGROUND >> ========== >> The demand for fax and fax services remains high. Fax Over IP >> (FoIP) is gaining momentum in the industry, but a number of issues >> remain that seriously impact interoperability and reliability. >> >> Issue: G.711 Fax Reliability: >> >> The ITU-T T.38 FoIP protocol standard overcame many of the issues >> experienced when transmitting a fax over G.711. >> However, many Service Providers use VoIP Gateways that do not support >> T.38. These Carriers pass fax traffic through their network using >> G.711. Fax traffic is highly sensitive to packet loss. The loss of >> fax packets (from latency or jitter for example) results in faxes to >> fail and be re-transmitted which uses more bandwidth and lowers the >> end user's satisfaction. Many carriers desire a FoIP solution that >> allows them to utilize their non- >> T.38 infrastructure to reliably carry fax traffic. >> >> Issue: T.38 Fax Interoperability: >> >> Many enterprises use T.38 for fax transmission. However, variations >> in the interpretation of the T.38 specification have lead to various >> interoperability challenges between vendors. There is speculation >> that improvements or profiles during session setup can alleviate many >> of these problems. >> >> >> WORKSHOP OVERVIEW >> ================= >> The SIP Forum FoIP Interoperability Workshop will bring together >> researchers, engineers, and service providers to exchange ideas, >> share experiences, and propose approaches to address FoIP problems. >> Particular focus will be on the use and applicability of SIP to >> address systemic or architectural problems. We will not be examining >> implementation errors. If the workshop identifies concrete proposals >> to improve FoIP that would require modifications to the underlying >> protocols, we will forward these proposals to the appropriate groups >> in the IETF, IEEE, or ITU- T. >> >> Topics of interest include but are not limited to: >> >> * Interoperability failures seen in the field or lab >> * Reliability or quality issues seen in the field or lab >> * Deployment experiences >> * Development experiences >> * Architectural principals >> * Proposals for achieving a higher degree of FoIP >> interoperability and/or FoIP reliability >> * Proposals for soliciting additional real-world feedback from >> implementers and service providers >> >> >> >> >> DISCUSSION MATERIALS >> ==================== >> The purpose of having position papers for this workshop is purely to >> help focus discussion and allow participants to get a feel for what >> other participants are thinking about. This is not a scholarly >> conference. PowerPoint presentations are fine! The goal of the >> workshop is not to publish high-quality research papers. The goal of >> the workshop is to publish a workshop report discussing the technical >> issues that are of the utmost importance to the industry, as well as >> a roadmap for how to address them. >> >> We encourage Individuals to submit position papers relevant to FoIP. >> Acceptable formats are IETF Internet Draft style (in HTML or plain >> text), IEEE Computer Society Proceedings Manuscripts style (in PDF), >> ACM Transactions style (in PDF), or presentation style (in PDF). The >> papers should be no longer than 6 pages if in IEEE or ACM style or 10 >> pages of text in Internet Draft style. There is no minimum length >> requirement. >> You may submit relevant, previously published works. If there is a >> copyright issue with the SIP Forum posting previously published >> papers, please give us a reference to the paper so we can direct >> participants to the appropriate publisher. >> >> Papers received by the submission deadline will be posted to the >> Workshop web site, unless the author(s) request withholding >> publication. The author(s) may retain copyright or assign it to the >> SIP Forum. If you are submitting a paper that already has a copyright >> assignment, such as an IEEE or ACM conference or journal paper, >> please apply the appropriate self-publication disclaimers demanded by >> those organizations. >> >> Submit your position paper using EasyChair at the following address: >> >> http://www.easychair.org/conferences/?conf=sffiw1 >> >> >> WORKSHOP FORMAT >> =============== >> The expectation is this will be a highly interactive workshop. In >> order to frame the conversation, the workshop chair will open the >> discussion. At the discretion of the workshop chair and dependent >> upon the quality and number of position papers received, the workshop >> chair may request formal presentations. Note that all position papers >> will be published on the SIP Forum web site, unless the author(s) >> request withholding publication. >> >> >> >> >> WORKSHOP FEES >> The workshop, including lunch, is free of charge to active >> participants. >> >> WORKSHOP CHAIR: Richard Shockey >> PROGRAM WHIP: Max Schroeder >> PROGRAM COMMITTEE: Eric Burger >> > _______________________________________________ > Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping > This list is for NEW development of the application of SIP Use > sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use > sip@xxxxxxxx for new developments of core SIP _______________________________________________ Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping This list is for NEW development of the application of SIP Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use sip@xxxxxxxx for new developments of core SIP
