2.1.6 Internet Fax (fax)

NOTE: This charter is a snapshot of the 46th IETF Meeting in Washington, DC. It may now be out-of-date. Last Modified: 29-Sep-99

Chair(s):

James Rafferty <jrafferty@worldnet.att.net>

Applications Area Director(s):

Keith Moore <moore@cs.utk.edu>
Patrik Faltstrom <paf@swip.net>

Applications Area Advisor:

Keith Moore <moore@cs.utk.edu>

Mailing Lists:

General Discussion:ietf-fax@imc.org
To Subscribe: ietf-fax-request@imc.org
In Body: In Body: subscribe
Archive: http://www.imc.org/ietf-fax/

Description of Working Group:

Facsimile (fax) serves as a reliable, inexpensive global communications service. As the Internet becomes pervasive, integrating fax and Internet services is appealing in terms of cost savings and opportunities for functional enhancements. This working group will pursue a review and specification for enabling standardized messaging-based fax over the Internet. It will also develop informal requirements for faxInternet gateways as a first step toward devising standards for session-based fax over the Internet. The messaging-based (via e-mail) service will be specified first, since it should produce useful results for the least additional technical effort.

Facsimile/Internet integration can be considered in terms of two user service models, in order of increasing technical difficulty:

o Messaging (as with electronic mail) having high latency o Session-based, for observed delivery, with or without capabilities negotiation

Within these models, a real-time (telephone network replacement) based service is considered to be a subset of the session-based model.

For interconnecting fax services over the dial-up telephone network and carriage of facsimile message data over the Internet, two types of interface systems are required:

o Internet/Dial-up Fax gateway, moving data from the Internet to classic or Internet-aware dial-up fax products and services

o Dial-up/Internet Fax gateway, moving data from classic or Internet-aware dial-up fax products and services to the Internet

The dominant fax communications mode in use today is a session-based connection operating in real-timeover the dial up telephone network; hence an Internet-based direct replacement service would potentially save significant long- distance telephone charges. However, it is believed that from a technical standpoint this service is the most difficult task to produce over the Internet, whereas an messaging-based service is likely to be the simplest. In addition, it is anticipated that the two services will ultimately utilize at least some common technical components. Therefore, this working group will initially review and specificy messaging-based fax over the Internet, using as much existing practice as possible.

The working group will take the following steps to specify a core fax-related messaging service over the Internet:

Terminology: Develop a shared set of terminology and definitions, to ensure a common framework for participants having differing backgrounds in Internet protocols and facsimile telecommunication.

Data Representations: Review existing facsimile- related Internet data specifications and accept, modify, replace or augment them, with particular attention to their encapsulation, such as via MIME.

Addressing and transport: Specify the mechanisms for addressing and receipt notification for facsimile data carried via Internet mail.

For session-oriented operation, the following specification will be created, as a basis for further work:

Operational constraints: Detail the operational constraints for achieving session-oriented use of messaging, tailored for timely delivery with the sender waiting for delivery confirmation. Existing protocols and data specifications will be used as much as possible.

The working group will take note of quality of service issues.

The working group will coordinate its activities with other facsimile- related standards bodies.

Goals and Milestones:

Jan 97

  

Submit Internet-Draft of data specifications

Jan 97

  

Submit Internet-Draft of terminology document

Feb 97

  

Submit Internet-Draft of messaging-related specification

Feb 97

  

Submit Internet-Draft of operational constraints document

Apr 97

  

Submit terminology document to IESG for publication

Apr 97

  

Submit data specifications to IESG for consideration as a standards track document

Jun 97

  

Submit messaging-related specification to IESG for consideration as a standards track document

Jun 97

  

Submit operational constraints document to IESG for publication as an Informational document

Internet-Drafts:

Request For Comments:

RFC

Status

Title

 

RFC2301

PS

File Format for Internet Fax

RFC2302

PS

Tag Image File Format (TIFF) - image/tiff MIME Sub-type Registration

RFC2303

PS

Minimal PSTN address format in Internet Mail

RFC2304

PS

Minimal FAX address format in Internet Mail

RFC2305

PS

A Simple Mode of Facsimile Using Internet Mail

RFC2306

 

Tag Image File Format (TIFF) - F Profile for Facsimile

RFC2542

 

Terminology and Goals for Internet Fax

RFC2530

PS

Indicating Supported Media Features Using Extensions to DSN and MDN

RFC2531

PS

Content feature schema for Internet fax

RFC2532

PS

Extended Facsimile Using Internet Mail

Current Meeting Report

James Rafferty
Chair, IETF Internet Fax WG

The final minutes follow:

Internet Fax WG - November 11, 1999
Chair: James Rafferty
Reported by: Glenn Parsons

James Rafferty presented the agenda and it was agreed.

Slides as presented by the chair at this meeting are available at the following URL: www.imc.org/ietf-fax/nov99-meeting.ppt

ITU Cooperation

James updated the group on the ITU-T SG8 meeting that happened in Maidenhead in September 1999. A delegation of three from ISOC attended representing the Fax WG. At this meeting T.37 Amd. 1 was finally approved.

This group sent a communication on Full Mode requirements and synchronization that was reviewed. It was noted that the ITU view cooperation as high priority. It was suggested that a follow-on communication should be sent in January for the next SG8 - the meeting agreed.

Last Call Drafts

The Full addressing document draft-ietf-fax-fulladdr-06.txt is in IETF last call to Proposed Standard. There is some concern that this is similar to the recent Antii URL document. The ADs confirmed that they have not yet looked at this - but it is on the list.

The WG expressed concern since other groups are starting to reference the minimal set document (RFC2303). The authors discussed the registration issues with IANA about 8 months ago.

Simple Mode to Draft

The editors have been working on refining the text for these documents to prepare them for Draft Standard. James gave an update on the current interoperability status.

Draft-ietf-fax-tiff-fx-03.txt (update of RFC 2301)

Lloyd McIntyre presented the additional clarifications to this draft since Oslo. These were agreed by the meeting.

- 5.2.3 JBIG Fax Profile (T.85) designated at default for T82Options instead of base JBIG (T.82)
- 2.2.2 & 6.2.1 Noted that metric equivalence resolutions (204x196 & 408x391) may be used in low and high resolutions

The slides from this presentation are available at the following URL: www.imc.org/ietf-fax/nov99-tiff-fx.ppt

Lloyd also indicated that an IPR statement has been submitted by Xerox for the TIFF-M profile. The license is available free of charge. There are currently two implementors independent of Xerox that possess licenses.

This draft is ready to move forward - James proposed that we issue a WG last call after this meeting. The meeting agreed.

There is a requirement to make TIFF adjustments for new T.30 tag additions. The issue is how to do this without breaking the standard. It was suggested that these could be added in as we move up the standards track. Our AD Keith said no, these should be put in a separate document. Another suggestion was to create an IANA registrations section for these new tags.

An interoperability report has previously been prepared by Rob Buckley and Lloyd McIntyre for TIFF-FX.

Draft-ietf-fax-service-v2-01.txt (Update of RFC 2305)

Co-author Ohno-san confirmed that there have been no revisions since Oslo. The FaxConnect reports are done, but more needs to be done in the reporting. Keith advised that the WG needs to ensure that at least two companies can interoperate with each feature. James will go back and summarize the details.

Ohno-san re-announced that theWIDE consortium has free code available implementing this. The URL will be reported on the list. Draft-ietf-fax-faxaddr-v2-00.txt & Draft-ietf-fax-minaddr-v2-00.txt

These drafts contain improvements of readability from the original RFCs. James noted, however, that we do not have extensive interoperability experience with some portions of these documents. James encouraged implementors to complete interoperability testing. It was proposed to send these documents for WG last call, the meeting agreed.

Other Drafts in Process

Draft-ietf-fax-coverpage-03.txt

Graham Klyne introduced this revision that contains very few changes. The WG is waiting on VPIM work on primary message content to guide us. Even though the content was changed to multipart/related from mulitpart/fax-message, the direction is still unclear. Th current view from Ned Freed is to use a new top level MIME/RFC822 header with content disposition.

This document describes three cases of how a cover page is included in a document. Dave Crocker suggests that this should be generic beyond just fax. For example, IPP is certainly interested.

The consensus is that this document is still immature. We want to make sure that this is coordinated amongst various communities (FAX, VPIM, IPP, IMPP, ...).

Draft-ietf-fax-feature-schema-v2-00.txt (updated RFC 2531)

Graham indicated that this has been updated based on the revised TIFF-FX. Several clarifications were made (e.g., TIFF-M description). However, a major change was made with the file structure.

The TIFF file structure was changed to not tie to the profiles but be somewhat more general. This is not compatible with the previous version. It is viewed as important to separate the file structure (i.e., ordering of the formats) from the profiles. The formats are: TIFF, TIFF limited (F), TIFF minimal (S), TIFF MRC, TIFF MRC limited

As a result of this change, the documents needs to be recycled at Proposed Standard. James suggested issuing a WG last call with intention to recycle at Proposed Standard. The meeting agreed.

Draft-ietf-fax-feature-t30-mapping-02.txt

There have been no changes in this draft. James proposed a WG last call with the intent to go to Informational. The meeting agreed.

New Drafts

Draft-ietf-fax-implementors-guide-00.txt

The authors were not at the meeting, so James reviewed this document. The intent is to clarify the implementation aspects of simple mode and extended mode. A list of open implementation issues at the end of document. This is a first draft and needs a lot more work.

Draft-ietf-fax-content-negotiation-00.txt

Graham introduced that the goal of this work is to enable content negotiation while ensuring normal behaviour with email and NO admin messages (i.e., messages sent only for this). It should work with simple & extended mode fax. The draft resulted from joint effort among several members of the WG and has benefited from other inputs including the ITU and prior drafts as well.

The current process flow is: sender sends initial message, receiver requests alternative, sender sends alternative. Note that the receiver chooses to start negotiation. This is a two roundtrip process. The optimized case here is to send after you know the end user's capabilities (e.g., from RESCAP or previous sends).

The sender uses MDN requests with the proposed content-alternative header containing a CONNEG syntax. The receiver sends capabilities and sender can choose if it wants to resend.

Graham confirmed that this is new and needs to be reviewed. The slides from this presentation are available at the following URL: www.imc.org/ietf-fax/nov99-conneg.pdf

Draft-ietf-fax-ffpim-00.txt

Dave Crocker introduced this Full mode service document. The goal is to point to the specifications (as simple mode does), that is this document is a placeholder until the supporting enhancements are made. Currently, the document is missing a security section -- there is a need to add privacy but no authentication.

Draft-ietf-fax-timely-delivery-00.txt

Graham Klyne introduced this document that allows end-to-end delivery of S&F fax within seconds using ESMTP extensions. The issue (and driving factor) is the lack of determinism - the sender has little control after the message is sent and the system has not set rules for time. The goal is to give control back to the sender. The document uses the proposed DELIVERBY ESMTP extension from Dan Newman.

This is still very preliminary. The slides from this presentation are available at the following URL: www.imc.org/ietf-fax/nov99-timely.pdf

Milestones

James reiterated his view from Oslo that this is the last meeting under the current charter. Cover Page & Implementor's guide will take some time to complete - but these are the only ones left.

We need a process for new work. James proposes a new Fax extensions WG with a new charter. Keith proposes that it makes sense to keep the existing WG and just re-charter. Others noted that this would make it easier to keep liaisons open with other groups.

Dave Crocker proposed a new charter that highlights the details of the new work to be done, they are:
- Gateway requirements (only T.37)
- Implementor's guide
- Full mode fax
- Security
- JBIG 2
- Extended mode to draft
- Gateway selection

The group started to discuss if we really want to standardize gateway behaviour. This and further discussion of the charter was deferred to the list.

The meeting confirmed that people are interested in working on this.
JBIG2 - Compact Image Representation

Lloyd McIntyre gave the meeting a introduction presentation on JBIG2 compression and data structures. JBIG2 approval in ISO/ITU is anticipated in Feb 2000.

JBIG 2 is very different from JBIG1 because of the quantum leap in compression. JBIG2 uses segmentation and type specific encoding. For example, text is treated as a connected component that is repeated. The segments are stored in MRC layers of TIFF-FX.

James expressed concern about potential IPR issues. ISO is so concerned with this that there is a low level version of this without IPR. Lloyd will ensure that all IPR on JBIG2 is made available by March.

TIFF-FX extensions are planned for March 2000. This would include new profiles T and M1, higher resolutions for all profiles except S and Feature Schema.

The slides from this presentation are available at the following URL: www.imc.org/ietf-fax/nov99-jbig.ppt

The meeting adjourned.

Slides

JBIG2 Compact Image Representation
Internet Fax WG Meeting Agenda
TIFF-FX Status