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SVG12: image/svg+xml gzip requirements

From: Bjoern Hoehrmann <derhoermi@gmx.net>
Date: Tue, 07 Dec 2004 15:39:35 +0100
To: www-svg@w3.org
Cc: ietf-types@iana.org
Message-ID: <41bfb9fb.357898203@smtp.bjoern.hoehrmann.de>

Dear Scalable Vector Graphics Working Group,

  The current http://www.w3.org/TR/SVG12/mimereg.html notes:

  SVG documents may be transmitted in compressed form using gzip
  compression. For systems which employ MIME-like mechanisms, such as
  HTTP, this is indicated by the Content-Transfer-Encoding header; for
  systems which do not, such as direct filesystem access, this is
  indicated by the filename extension and by the Macintosh File Type
  Codes. In addition, gzip compressed content is readily recognised by
  the initial byte sequence as described in RFC1952 section 2.3.1. 

Unless the document is meant to introduce a new HTTP header, this is
clearly false, RFC 2616 explicitly notes that Content-Transfer-Encoding
is not used in HTTP/1.1, please change the text to refer to an actual
HTTP header.

I am puzzled by the last sentence here, the text seems to suggest that
implementations of the image/svg+xml MIME type are required to sniff for
gzip compressed content so that much of the ill-formed SVG content


where content is compressed but the compression is not indicated through
the relevant HTTP headers would actually be conforming. This is not
accetable as it is inconsistent with the Authoritative Metadata TAG
finding http://www.w3.org/2001/tag/doc/mime-respect.html and RFC 3023
and 2616 which do not include such a requirement which means that such
content would not work in general purpose XML processors which means
that use of the +xml convention for image/svg+xml would not be

Please change the text to clearly indicate that this is not allowed and
that SVG Viewers are required to treat such content as ill-formed XML
and thus reject it entirely.

Björn Höhrmann · mailto:bjoern@hoehrmann.de · http://bjoern.hoehrmann.de
Weinh. Str. 22 · Telefon: +49(0)621/4309674 · http://www.bjoernsworld.de
68309 Mannheim · PGP Pub. KeyID: 0xA4357E78 · http://www.websitedev.de/ 
Received on Tuesday, 7 December 2004 14:39:57 UTC

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