As per Relevance of the word parameter, we have this rfc below:
Network Working Group M.
Request for Comments: 3236 Planetfred, Inc
Category: Informational P.
Ericsson Mobile
January 2002
The 'application/xhtml+xml' Media
Status of this
This memo provides information for the Internet community. It
not specify an Internet standard of any kind. Distribution of
memo is unlimited
Copyright
Copyright (C) The Internet Society (2002). All Rights Reserved
This document defines the 'application/xhtml+xml' MIME media type
XHTML based markup languages; it is not intended to obsolete
previous IETF documents, in particular RFC 2854 which
'text/html'.
1.
In 1998, the W3C HTML working group began work on reformulating
in terms of XML 1.0 [XML] and XML Namespaces [XMLNS]. The first
of that work concluded in January 2000 with the publication of
XHTML 1.0 Recommendation [XHTML1], the reformulation for HTML 4.01
[HTML401].
Work continues in the Modularization of XHTML
[XHTMLM12N], the decomposition of XHTML 1.0 into modules that can
used to compose new XHTML based languages, plus a framework
supporting this composition
This document only registers a new MIME media type
'application/xhtml+xml'. It does not define anything more than
required to perform this registration
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
This document follows the convention set out in [XMLMIME] for
MIME subtype name; attaching the suffix "+xml" to denote that
entity being described conforms to the XML syntax as defined in
1.0 [XML].
This document was prepared by members of the W3C HTML working
based on the structure, and some of the content, of RFC 2854,
registration of 'text/html'. Please send comments to www
html@w3.org, a public mailing list (requiring subscription)
archives at .
2. Registration of MIME media type application/xhtml+
MIME media type name:
MIME subtype name: xhtml+
Required parameters:
Optional parameters
This parameter has identical semantics to the charset
of the "application/xml" media type as specified in [XMLMIME].
See Section 8 of this document
Encoding considerations
See Section 4 of this document
Security considerations
See Section 7 of this document
Interoperability considerations
XHTML 1.0 [XHTML10] specifies user agent conformance rules
dictate behaviour that must be followed when dealing with,
other things, unrecognized elements
With respect to XHTML Modularization [XHTMLMOD] and the
of XHTML based languages (referred to as XHTML family members
that are not XHTML 1.0 conformant languages, it is possible
'application/xhtml+xml' may be used to describe some of
documents. However, it should suffice for now for the purposes
interoperability that user agents
'application/xhtml+xml' content use the user agent
rules in [XHTML1].
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
Although conformant 'application/xhtml+xml' interpreters
expect that content received is well-formed XML (as defined
[XML]), it cannot be guaranteed that the content is valid
(as defined in [XHTML1]). This is in large part due to
reasons in the preceding paragraph
Published specification
XHTML 1.0 is now defined by W3C Recommendation; the
published version is [XHTML1]. It provides for the description
some types of conformant content as "text/html", but also doesn'
disallow the use with other content types (effectively
for the possibility of this new type).
Applications which use this media type
Some content authors have already begun hand and tool authoring
the Web with XHTML 1.0. However that content is
described as "text/html", allowing existing Web browsers
process it without reconfiguration for a new media type
There is no experimental, vendor specific, or personal
predecessor to 'application/xhtml+xml'. This new type is
registered in order to allow for the expected deployment of
on the World Wide Web, as a first class XML application
authors can expect that user agents are conformant XML 1.0 [XML
processors
Additional information
Magic number
There is no single initial byte sequence that is always
for XHTML files. However, Section 5 below gives
guidelines for recognizing XHTML files. See also section 3.1
[XMLMIME].
File extension
There are three known file extensions that are currently in
for XHTML 1.0; ".xht", ".xhtml", and ".html".
It is not recommended that the ".xml" extension (defined
[XMLMIME]) be used, as web servers may be configured
distribute such content as type "text/xml"
"application/xml". [XMLMIME] discusses the unreliability
this approach in section 3. Of course, should the
desire this behaviour, then the ".xml" extension can be used
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
Macintosh File Type code:
Person & email address to contact for further information
Mark Baker
Intended usage:
Author/Change controller
The XHTML specifications are a work product of the World Wide
Consortium's HTML Working Group. The W3C has change control
these specifications
3. Fragment
URI references (Uniform Resource Identifiers, see [RFC2396]
updated by [RFC2732]) may contain additional reference information
identifying a certain portion of the resource. These URI
end with a number sign ("#") followed by an identifier for
portion (called the "fragment identifier"). Interpretation
fragment identifiers is dependent on the media type of the
result
For documents labeled as 'text/html', [RFC2854] specified that
fragment identifier designates the correspondingly named element
these were identified by either a unique id attribute or a
attribute for some elements. For documents described with
application/xhtml+xml media type, fragment identifiers share the
syntax and semantics with other XML documents, see [XMLMIME],
5.
At the time of writing, [XMLMIME] does not define syntax
semantics of fragment identifiers, but refers to "XML
Language (XPointer)" for a future XML fragment
mechanism. The current specification for XPointer is available
http://www.w3.org/TR/xptr. Until [XMLMIME] gets updated,
identifiers for XHTML documents designate the element with
corresponding ID attribute value (see [XML] section 3.3.1); any
element with the "id" attribute
4. Encoding
By virtue of XHTML content being XML, it has the same
when sent as 'application/xhtml+xml' as does XML. See [XMLMIME],
section 3.2.
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
5. Recognizing XHTML
All XHTML documents will have the string "
of the document. Some will also begin with an XML declaration
begins with "indicate an
document. All conforming XHTML 1.0 documents will include an
document type declaration with the root element type 'html'.
XHTML Modularization provides a naming convention by which a
identifier for an external subset in the document type declaration
a conforming document will contain the string "//DTD XHTML".
while some XHTML based languages require the doctype declaration
occur within documents of that type, such as XHTML 1.0, or
Basic (http://www.w3.org/TR/xhtml-basic), it is not the case that
XHTML based languages will include it
All XHTML files should also include a declaration of the
namespace. This should appear shortly after the string "
should read 'xmlns="http://www.w3.org/1999/xhtml"'.
6. Charset default
By virtue of all XHTML content being XML, it has the
considerations when sent as 'application/xhtml+xml' as does XML.
[XMLMIME], section 3.2.
7. Security
The considerations for "text/html" as specified in [TEXTHTML] and
for 'application/xml' as specified in [XMLMIME], also hold
'application/xhtml+xml'.
In addition, because of the extensibility features for XHTML
provided by XHTML Modularization, it is possible
'application/xhtml+xml' may describe content that has
implications beyond those described here. However, if the user
follows the user agent conformance rules in [XHTML1], this
will be ignored. Only in the case where the user agent
and processes the additional content, or where further processing
that content is dispatched to other processors, would security
potentially arise. And in that case, they would fall outside
domain of this registration document
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
8. The "profile" optional
This parameter is meant to solve the short-term problem of using
media type based content negotiation (such as that done with the
"Accept" header) to negotiate for a variety of XHTML based languages
It is intended to be used only during content negotiation. It is
expected that it be used to deliver content, or that origin
servers have any knowledge of it (though they are welcome to). It
primarily targeted for use on the network by proxies in the
chain that manipulate data formats (such as transcoders).
The parameter is intended to closely match the semantics of
"profile" attribute of the HEAD element as defined in [HTML401]
(section 7.4.4.3), except it is applied to the document as a
rather than just the META elements. More specifically, the value
the profile attribute is a URI that can be used as a name to
a language. Though the URI need not be resolved in order to
useful as a name, it could be a namespace, schema, or a
specification
As an example, user agents supporting only XHTML Basic (
http://www.w3.org/TR/xhtml-basic) currently have no standard means
convey their inability to support the additional functionality
XHTML 1.0 [XHTML1] that is not found in XHTML Basic. While
Basic user agent conformance rules (which are identical to XHTML 1.0)
provide some guidance to its user agent implementators for
some additional content, the additional content in XHTML 1.0 that
not part of XHTML Basic is substantial, making those
rules insufficient for practical processing and rendering to the
user. There is also the matter of the potentially substantial
on the user agent in receiving and parsing this additional content
The functionality afforded by this parameter can also be
with at least two other more general content description frameworks
the "Content-features" MIME header described in RFC 2912, and
from the WAPforum (see http://www.wapforum.org/what/technical.htm).
At this time, choosing one of these solutions would require
the other, as interoperability between the two has not been defined
For this reason, it is suggested that this parameter be used
such time as that issue has been addressed
An example use of this parameter as part of a HTTP GET
would be
Accept: application/xhtml+xml
profile="http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
9. Author's
Mark A.
Planetfred, Inc
44 Byward Market, Suite 240
Ottawa, Ontario, CANADA. K1N 7A
Phone: +1-613-789-1818
EMail: mbaker@planetfred.
EMail: distobj@acm.
Peter
Ericsson Mobile
Phone: +464-619-3000
EMail: Peter.Stark@ecs.ericsson.
10.
[HTML401] Raggett, D., et al., "HTML 4.01 Specification", W3
Recommendation. Available
(
).
[MIME] Freed, N. and N. Borenstein, "Multipurpose Internet
Extensions (MIME) Part Two: Media Types", RFC 2046,
November 1996.
[URI] Berners-Lee, T., Fielding, R. and L. Masinter, "
Resource Identifiers (URI): Generic Syntax", RFC 2396,
August 1998.
[XHTML1] "XHTML 1.0: The Extensible HyperText Markup Language:
Reformulation of HTML 4 in XML 1.0", W3C Recommendation
Available at .
[XML] "Extensible Markup Language (XML) 1.0", W3
Recommendation. Available at
xml> (or ).
[TEXTHTML] Connolly, D. and L. Masinter, "The 'text/html'
Type", RFC 2854, June 2000.
[XMLMIME] Murata, M., St.Laurent, S. and D. Kohn, "XML
Types", RFC 3023, January 2001.
[XHTMLM12N] "Modularization of XHTML", W3C Recommendation.
at:
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RFC 3236 The 'application/xhtml+xml' Media Type January 2002
11. Full Copyright
Copyright (C) The Internet Society (2002). All Rights Reserved
This document and translations of it may be copied and furnished
others, and derivative works that comment on or otherwise explain
or assist in its implementation may be prepared, copied,
and distributed, in whole or in part, without restriction of
kind, provided that the above copyright notice and this paragraph
included on all such copies and derivative works. However,
document itself may not be modified in any way, such as by
the copyright notice or references to the Internet Society or
Internet organizations, except as needed for the purpose
developing Internet standards in which case the procedures
copyrights defined in the Internet Standards process must
followed, or as required to translate it into languages other
English
The limited permissions granted above are perpetual and will not
revoked by the Internet Society or its successors or assigns
This document and the information contained herein is provided on
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
Funding for the RFC Editor function is currently provided by
Internet Society
Baker & Stark Informational [Page 8]
if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.
RFC documents can be found at I.E.T.F.
Relevance System Copyright © 2002 Spectrum WorldResearch
other technical nosh by ServerMasters Corporation
collaboration of BobX
