Network Working Group J. Collins Internet-Draft Bitstream Inc. Document: 14 Nov 2000 expires: 14 May 2001 Category: Informational Portable Font Resource (PFR) - application/font-tdpfr MIME Sub-type Registration Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 1. Abstract This document describes the registration of the MIME sub-type application/font-tdpfr. The encoding is defined by [PFR]. A PFR contains a set of glyph shapes. Each glyph shape is associated with a character code. The PFR format is designed to be both compact and platform-independent. It is intended to facilitate accurate rendering of fonts in all environments whether or not they have the required fonts already installed. 2. Conventions used in this document The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this Collins Informational [Page 1] Internet Draft PFR November 2000 document are to be interpreted as described in RFC-2119 [REQ]. 3. Overview This document describes the registration of the MIME sub-type application/font-tdpfr. The encoding is defined by [PFR]. 4. PFR Definition PFR (Portable Font Resource) is defined by Bitstream Inc. in [PFR]. The documentation can be obtained from Bitstream at: Bitstream Inc. 215 First Street Cambridge MA 02142 U.S.A. Phone: +1 617 497 6222 Fax: +1 617 868 0784 A copy of this specification can also be found at: http://www.bitstream.com/pfrspec/index.html While a brief scope and feature description is provided in this section as background information, the reader is directed to the original PFR specification [PFR] to obtain complete feature and technical details. 4.1 PFR Scope A PFR contains a set of glyph shapes. Each glyph shape is associated with a character code. The PFR format is designed to be both compact and platform-independent. It is intended to facilitate accurate rendering of fonts in environments whether or not they have the required fonts already installed. The glyph shape definitions in a PFR are resolution-independent. This allows glyph definitions to be displayed or printed on devices with a wide variety of resolutions. It also allows glyphs to be rendered at any size. 4.1 PFR Features Some of the features of the PFR format are: - Compact representation of glyph shapes - Independent of byte order and operating system - Independent of output device resolution Collins Informational [Page 2] Internet Draft PFR November 2000 - Fully scalable to any glyph size - Optional inclusion of bitmap glyph images - Adopted as the font standard by DAVIC, DVB, and DTG 5. Comments This document is submitted by J. Collins, Bitstream Inc. All comments should be directed to . 6. MIME Definition The PFR media type has been previously registered with IANA as application/vnd.truedoc. In view of its subsequent widespread adoption as a standard font format by multiple standards bodies who have relationships with the Internet community, Bitstream has been asked to re-register this media type within the IETF tree. 7. IANA Registration To: ietf-types@iana.org Subject: Registration of Standard MIME Media type application/font-tdpfr MIME media type name: application MIME subtype name: font-tdpfr Required parameters: none Optional parameters: none Encoding considerations: Binary or base 64 required Security considerations: PFR uses a structure that can store glyph image data and encoding arrays. The fields defined in the PFR specification are of a descriptive nature and provide information that is useful to facilitate viewing and rendering of glyph images by a recipient. As such, the fields currently defined in the PFR specification do not in themselves create additional security risks, since the fields are not used to induce any particular behavior by the recipient application. PFR has an extensible structure, so that it is theoretically possible that fields could be defined in the future which could be used to induce particular actions on the part of the recipient, Collins Informational [Page 3] Internet Draft PFR November 2000 thus presenting additional security risks, but this type of capability is not supported in the referenced PFR specificaton. Indeed, the definition of fields that would include such processing instructions is inconsistent with the goals and spirit of the PFR specification. Interoperability considerations: none Published specification: The specification for this content type is available on request from: Bitstream Inc. 215 First Street Cambridge MA 02142 U.S.A. Phone: +1 617 497 6222 Fax: +1 617 868 0784 A copy of this specification can also be found at: http://www.bitstream.com/pfrspec/index.html Applications which use this media type: Netscape Communicator, Bitstream WebFont Maker, Hexmac Typograph Additional information: None Magic number(s): 50 46 52 30 hex File extension(s): PFR Macintosh File Type Code(s): Creator: 'b$pw' Type: 'PFR ' Person to contact for further information: "John Collins" Intended usage: common Author/Change controller: "John Collins" 8. References [REQ] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. Collins Informational [Page 4] Internet Draft PFR November 2000 [MIME1] N. Freed and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, Innosoft, First Virtual, Nov 1996. [MIME4] N. Freed and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures", RFC 2048, Innosoft, First Virtual, Nov 1996. [PFR] Bitstream Inc. "PFR Specification", http://www.bitstream.com/pfrspec/index.html 9. Author's Address John Collins Bitstream Inc. 215 First Street Cambridge, MA 02142 Phone: +1 617 520 8401 Fax: +1 617 868 0784 EMail: jcollins@bitstream.com Document expires 14 May, 2001 Collins Informational [Page 5]