HTTP/1.1 200 OK Date: Tue, 09 Apr 2002 02:20:46 GMT Server: Apache/1.3.20 (Unix) Last-Modified: Tue, 29 Sep 1998 15:15:00 GMT ETag: "2ed974-4070-3610f974" Accept-Ranges: bytes Content-Length: 16496 Connection: close Content-Type: text/plain Fax working group Lloyd McIntyre INTERNET-DRAFT Xerox Corporation Category: Work-in-progress Graham Klyne 5GM/Content Technology Ltd September 1998 Expires: March 1999 Content feature schema for Internet fax Status of this memo This document is an Internet-Draft. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as ``work in progress''. To view the entire list of current Internet-Drafts, please check the "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow Directories on ftp.is.co.za (Africa), ftp.nordu.net (Northern Europe), ftp.nis.garr.it (Southern Europe), munnari.oz.au (Pacific Rim), ftp.ietf.org (US East Coast), or ftp.isi.edu (US West Coast). [[INTENDED STATUS: This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.]] Copyright Notice Copyright (C) The Internet Society 1998. All Rights Reserved. Abstract This document defines a content feature schema that is a profile of the media feature registration mechanisms [1,2,3] for use in performing capability identification between extended Internet fax systems [5]. McIntyre/Klyne Work-in-progress [Page 1] RFC nnnn Content feature schema for Internet fax September 1998 This document does not describe any specific mechanisms for communicating capability information, but does presume that any such mechanisms will transfer textual values. It specifies a textual format to be used for describing Internet fax capability information. Table of contents 1. Introduction ............................................3 1.1 Organization of this document 3 1.2 Terminology and document conventions 3 1.3 Revision history 4 1.4 Unfinished business 4 2. Fax feature schema syntax ...............................4 3. Internet fax feature tags ...............................4 3.1 Image Size 5 3.2 Resolution 5 3.3 Media type 5 3.4 Paper Size 6 3.5 Color and greyscale 6 3.6 Coding 7 3.7 Color model 7 3.8 Preferred units 7 4. Examples ................................................7 4.1 Simple fax machine 8 4.2 Grey-scale fax machine 8 4.3 Full-colour fax machine 8 4.4 PC-based e-mail recipient 8 5. Security considerations .................................8 6. Full copyright statement ................................8 7. Acknowledgements ........................................8 8. References ..............................................9 9. Authors' addresses ......................................10 Appendix A: Feature registrations ..........................10 1. Introduction This document defines a content feature schema that is a profile of the media feature registration mechanisms [1,2,3] for use in performing capability identification between extended Internet fax systems [5]. This document does not describe any specific mechanisms for communicating capability information, but does presume that any such mechanisms will transfer textual values. It specifies a textual format to be used for describing Internet fax capability information. The range of capabilities that can be indicated are based on those defined for Group 3 facsimile [6]. A companion document [4] McIntyre/Klyne Work-in-progress [Page 2] RFC nnnn Content feature schema for Internet fax September 1998 describes the relationship and mapping between this schema and Group 3 fax capabilities. 1.1 Organization of this document Section 2 specifies the overall syntax for fax feature descriptions by reference to the media feature registration and syntax documents [1,2]. Section 3 enumerates the feature tags that MUST be recognized and processed by extended Internet fax systems, according to their capabilities. Appendix A contains additional feature tag registrations for media features that are specific to fax and for which no applicable registration already exists. These are presented in the form prescribed by the media feature registration procedure [1]. 1.2 Terminology and document conventions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. The term "eifax system" is used to describe any software, device or combination of these that conforms to the specification "Extended Facsimile Using Internet Mail" [5]. NOTE: Comments like this provide additional nonessential information about the rationale behind this document. Such information is not needed for building a conformant implementation, but may help those who wish to understand the design in greater depth. 1.3 Revision history 00a 28-Sep-1998 Initial draft. 1.4 Unfinished business . Review terminology (especially eifax). . Finalize feature set . Supply examples . Supply new feature registrations McIntyre/Klyne Work-in-progress [Page 3] RFC nnnn Content feature schema for Internet fax September 1998 2. Fax feature schema syntax The syntax for the fax feature schema is described by "An algebra for describing media feature sets" [2]. This in turn calls upon media feature tags that may be registered according to the procedure described in "Media Feature Tag Registration Procedure" [1]. ??Note: The document name for [2] will change to "A syntax for describing media feature sets". Note: Media feature registration provides a base vocabulary of features that correspond to media handling capabilities. The feature set syntax provides a mechanism and format for combining these to describe combinations of features that may be handled by eifax systems. 3. Internet fax feature tags This section enumerates and briefly describes the feature tags that MUST be recognized and processed by eifax systems and for which a value SHOULD be offered in any capability announcement, according to their capabilities. That is, a number of feature tags are presented below that an eifax system is expected to be able to recognize its ability or non- ability to handle. Definitive descriptions of feature tags are indicated by reference to their registration per the 'conneg' registration procedure (some of which are appended to this document) NOTE: The presence of a feature tag in this list does not mean that an eifax system must have that capability; rather, it must recognize the feature tag and relate it to the capabilities that it does have. Further, an eifax system is not prevented from recognizing and offering additional feature tags. The list below is intended to provide a minimum vocabulary which all eifax systems can use in a consistent fashion. 3.1 Image Size Feature tag name Legal values ---------------- ------------ pix-x (>0) pix-y (>0) Reference: "Media Features for Display, Print, and Fax" [3]. McIntyre/Klyne Work-in-progress [Page 4] RFC nnnn Content feature schema for Internet fax September 1998 [[[The use of pixels as a measure of fax image size is currently under discussion: should we use pixels or some physical unit of measure?]]] 3.2 Resolution Feature tag name Legal values ---------------- ------------ dpi (>0) dpi-xyratio (>0) Reference: "Media Features for Display, Print, and Fax" [3], and this document appendix A. [[[The use of resolution and x/y resolution ratio values versus using separate x- and y- resolutions is currently under discussion]]] 3.3 Media type Feature tag name Legal values ---------------- ------------ ua-media screen screen-paged stationery transparency envelope envelope-plain continuous Reference: "Media Features for Display, Print, and Fax" [3]. [[[The relevance of media type to Internet fax is currently under discussion. I think it is not relevant.]]] 3.4 Paper Size Feature tag name Legal values ---------------- ------------ paper-size A4 A3 B4 letter legal Reference: "Media Features for Display, Print, and Fax" [3]. [[[There may be some conflict or interaction between this and 'image size' above.]]] McIntyre/Klyne Work-in-progress [Page 5] RFC nnnn Content feature schema for Internet fax September 1998 3.5 Color and greyscale Feature tag name Legal values ---------------- ------------ grey (Typically 2,16,256,65536,16777216) color (Typically 16,256,65536,16777216) Reference: "Media Features for Display, Print, and Fax" [3]. NOTE: a bi-level (i.e. black-and-white only) fax image or capability is indicated by the feature value 'grey=2'. This is indicates the rendering capabilities of a recipient or requirements of a document, and does not of itself indicate a coding scheme. 3.6 Coding Feature tag name Legal values ---------------- ------------ image-coding MH MR MMR JBIG JBIG-LO JBIG-T43 JPEG image-interleave Strip Plane color-subsampling MRC-level [0-7] MRC-strip Fullpage Line256 Reference: this document, appendix A. 3.7 Color model Feature tag name Legal values ---------------- ------------ custom-illuminant custom-gamut Reference: this document, appendix A. McIntyre/Klyne Work-in-progress [Page 6] RFC nnnn Content feature schema for Internet fax September 1998 3.8 Preferred units Feature tag name Legal values ---------------- ------------ preferred-unit metric inch Reference: this document, appendix A. 4. Examples <<>> <<> 4.1 Simple fax machine 4.2 Grey-scale fax machine 4.3 Full-colour fax machine 4.4 PC-based e-mail recipient 5. Security considerations <<>> 6. Full copyright statement Copyright (C) The Internet Society 1998. All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. McIntyre/Klyne Work-in-progress [Page 7] RFC nnnn Content feature schema for Internet fax September 1998 This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 7. Acknowledgements <<>> 8. References [1] "Media Feature Tag Registration Procedure" Koen Holtman, TUE Andrew Mutz, Hewlett-Packard Ted Hardie, NASA Internet draft: Work in progress, July 1998. [2] "A syntax for describing media feature sets" Graham Klyne, 5GM/Content Technologies Internet draft: " Work in progress, September 1998. [3] "Media Features for Display, Print, and Fax" Larry Masinter, Xerox PARC Koen Holtman, TUE Andrew Mutz, Hewlett-Packard Dan Wing, Cisco Systems Internet draft: Work in progress, September 1998. [4] "Internet fax feature mapping from Group 3 fax" Lloyd McIntyre, Xerox Corporation Graham Klyne, 5GM/Content Technologies Internet draft: Work in progress, August 1998. [5] "Extended Facsimile Using Internet Mail Larry Masinter, Xerox Corporation Dan Wing, Cisco Systems Internet draft: Work in progress, September 1998. [6] "Procedures for document facsimile transmission in the general switched telephone network" ITU-T Recommendation T.30 International Telecommunications Union July 1996 McIntyre/Klyne Work-in-progress [Page 8] RFC nnnn Content feature schema for Internet fax September 1998 9. Authors' addresses Lloyd McIntyre Xerox Corporation Mailstop PAHV-305 3400 Hillview Ave. Palo Alto, CA 94304 USA Telephone: +1-650-813-6762 Facsimile: +1-650-845-2340 E-mail: Lloyd.McIntyre@pahv.xerox.com Graham Klyne 5th Generation Messaging Ltd. Content Technologies Ltd. 5 Watlington Street Forum 1, Station Road Nettlebed Theale Henley-on-Thames, RG9 5AB Reading, RG7 4RA United Kingdom United Kingdom. Telephone: +44 1491 641 641 +44 118 930 1300 Facsimile: +44 1491 641 611 +44 118 930 1301 E-mail: GK@ACM.ORG Appendix A: Feature registrations [[[This appendix contains registrations of media features, that are specific to fax and for which no applicable registration already exists.]]] McIntyre/Klyne Work-in-progress [Page 9]