Internet DRAFT - draft-collins-pfr
draft-collins-pfr
Network Working Group J. Collins
Internet-Draft Bitstream Inc.
Document: <draft-collins-pfr-00.txt> 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 <jcollins@bitstream.com>.
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" <jcollins@bitstream.com>
Intended usage: common
Author/Change controller:
"John Collins" <jcollins@bitstream.com>
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]
