The World Wide Web Consortium

and Standards

C. M. Sperberg-McQueen,
Co-chair, W3C XML Schema Working Group
Co-chair, W3C XML Coordination Group
Domain Lead, W3C Architecture Domain

XML World 2001

San Francisco, California

27 November 2001

TOC | First

Abstract

W3C is the birthplace of XML, but there's more to XML than one specification. The XML family of technologies is largely developed within the W3C XML Activity. Michael will provide an overview of the current and planned work of the W3C XML Activity, and address questions related to specific topics including XML Schema, XML Query, and XLink.


W3C 

Overview

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W3C 

XML: the simple idea

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At heart, XML is a simple idea:
  • Text is not just a sequence of characters.
W3C 

XML: the simple idea

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At heart, XML is a simple idea:
  • Text is not just a sequence of characters.
  • Text is not just an arbitrary mixture of characters with commands.
W3C 

XML: the simple idea

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At heart, XML is a simple idea:
  • Text is not just a sequence of characters.
  • Text is not just an arbitrary mixture of characters with commands.
  • Text has structure.
W3C 

XML: the simple idea

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At heart, XML is a simple idea:
  • Text is not just a sequence of characters.
  • Text is not just an arbitrary mixture of characters with commands.
  • Text has structure.
Information has structure.
Information formats should expose that structure.
W3C 

XML: the simple idea

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If information formats expose the structure of information, then:
  • Information can be richer, more variable, more subtle.
  • Software can be stupider simpler, cheaper, faster.
If we can't have intelligent software, let's at least have well-informed software.
W3C 

XML: the simple idea

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Nothing in XML is new.
It all (start-tags, end-tags, elements, attributes, tree structure, entities, document grammars) came straight out of SGML.
The original goals of the XML activity were:
  • make SGML usable on the Web
  • add structure to Web documents
  • be simple (25 pp.), clean (validity)
W3C 

Growth of XML

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XML has grown beyond its original goals:
  • make SGML and HyTime, and DSSSL usable on the Web
  • add structure to Web documents and data
W3C 

Growth of XML

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  • allow arbitrary data to be exposed on Web in XML
  • make XML usable in specific applications:
    • improve metalanguage for defining languages
    • query
    • authenticate with digital signature
    • canonicalize so signatures are more robust
    • use XML for program-to-program communication
    • use XML as the basis for Web Services
W3C 

What's new at W3C?

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W3C 

Who is the W3C?

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The World Wide Web Consortium is a member-supported organization which creates Web standards.
Our mission:
W3C 

Who is the W3C?

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The World Wide Web Consortium is a member-supported organization which creates Web standards.
Our mission:
to lead the Web to its full potential.
W3C 

W3C goals and operating principles

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W3C 

Organization of work in W3C

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Domains and Activities:
  • Architecture Domain
  • Technology and Society Domain
  • Document Formats Domain
  • Interaction Domain
  • Web Accessibility Initiative
W3C 

Architecture Domain

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W3C 

Technology and Society Domain

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W3C 

Document Formats Domain

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W3C 

User Interface Domain

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W3C 

Web Accessibility Initiative

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W3C 

The W3C Rec Track

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W3C 

The W3C Rec Track

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W3C 

XML Core WG

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Chairs: Paul Grosso, Arnaud Le Hors
Specifications:
  • XML 1.0 Second Edition, ed. Eve Maler (XML 1.02e) (Recommendation)
  • XML updates for Unicode 3.x (XML Blueberry) (Requirements out, draft out)
  • XML Information Set (Rec)
  • XML Inclusions (XInclude) (Last Call completed)
  • Errata for existing specs
Pending:
  • XML Namespaces 1.1
  • Classification of XML Processors
W3C 

XML Linking

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Chair: Henry Thompson
Two Recommendations:
  • XLink (standoff links, multi-ended links, better role labeling)
  • XML Base (relative URI support)
One Candidate Recommendation:
  • XPointer (addressing into XML)
W3C 

XML Schema

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Chairs: Dave Hollander, Michael Sperberg-McQueen
XML Schema, parts 0, 1, and 2 a W3C Recommendation.
Pending:
  • entities/special characters work
  • formal description of XML Schema
  • work on test suite
W3C 

XML Schema Highlights

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Like DTDs, but:
  • in XML document syntax
  • coherent account of schema validation across multiple namespaces
  • modular construction of vocabularies
  • full validation, partial validation (black boxes, white boxes)
  • simple datatypes
  • inheritance
W3C 

XML Query

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Chair: Paul Cotton
Toward an XML Query language for all XML data:
  • XQuery 1.0 and XPath 2.0 Data Model
  • XQuery 1.0 and XPath 2.0 Functions and Operators
  • XML Query Use Cases
  • XQuery 1.0 Formal Semantics
  • XQuery 1.0: An XML Query Language
  • XML Syntax for XQuery 1.0 (XQueryX)
W3C 

XML Query Highlights

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  • element selection (XPath++)
  • strong static typing
  • dynamic type checking
  • keyword syntax and XML syntax
  • generate arbitrary XML results
W3C 

DOM

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Chair: Philippe Le Hégaret
Recommendations: Document Object Model (DOM) Level 2
  • Core
  • Views
  • Events
  • Style
  • Traversal and Range
W3C 

DOM, continued

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Working drafts:
  • Level 2 HTML DOM
  • Level 3 Core
  • Level 3 Views and Formatting
  • Level 3 Abstract Schemas and Load and Save
  • Level 3 Events
W3C 

DOM Highlights

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DOM provides
  • an intelligent API for document manipulation
  • browser-independence* of scripting code
  • crucial tool for power users and system integrators (this means you)
  • support for editors ...
W3C 

XML Protocols

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Chair: David Fallside
Goal: create a simple foundation for program to program communication using XML.
Recent documents:
  • Requirements document
  • XML Protocol Abstract Model
  • SOAP 1.2 Working Drafts
    • Part 1: Messaging Framework
    • Part 2: Adjuncts
W3C 

XSL

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Chair: Sharon Adler
XSLT a W3C Recommendation since November 1999
XSL (aka XSL FO) now also a Recommendation
Work underway for XPath 2, XSLT 2 (extensibility, XML Schema type support)
W3C 

Semantic Web

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Goals: define
  • enabling standards (RDF/XML)
  • and support technologies (software)
to facilitate the creation of machine readable metadata on the Web for more effective
  • discovery,
  • automation, and
  • integration
of networked information.
  • Semantic Web Activity headed by Eric Miller
  • Advanced Development headed by Ralph Swick
W3C 

RDF Core WG

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Chairs: Brian McBride, Dan Brickley
Resource Description Framework: a low-level model for semantic structures.
Basic model: labeled directed graph.
Current work:
  • RDF Model and Syntax (Recommendation)
  • RDF Schema (Candidate Rec)
W3C 

RDF -- the basics

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To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!
W3C 

RDF -- the basics

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To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!
So -- define a vocabulary ...
W3C 

RDF -- the basics

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To describe a resource, you need a vocabulary in which to describe it.
The problem is that in a world-wide Web with universal access, we cannot rationally assume that we know in advance everything anyone might wish to say.
No closed-world assumptions!
So -- define a vocabulary ... but also specify a more fundamental extensible semantic system in which it is defined.
W3C 

RDF -- the minimum

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To say something about something is to describe some property/ies of your subject. You need at least:
  • a way to name the subject (URI)
  • a way to identify the property you are giving (label, property name)
  • a way to give the value of a property (literal, or URI)
W3C 

Intellectual property

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Does anyone like software patents?
Can anyone do anything about them?
And what do we do in the meantime?
W3C 

W3C Patent Policy

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The key components of the draft W3C patent policy:
  • disclosure (no* submarine patents)
  • commitment in advance to terms
  • essential technology
  • possible opt-out
  • viral effect
Other components:
  • royalty-free vs. `reasonable and non-discriminatory' terms
W3C 

Some myths and facts

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  • "W3C is loosening its policy."
  • No, W3C is tightening its policy.
W3C 

Myth/Fact No. 2

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  • "W3C used to grant royalty-free licences, and now you're planning to extract royalties."
  • No, W3C has never had licensing terms attached to implementation of W3C Recs.
    W3C documents and open-source software continue to be available on the same terms as before.
W3C 

Myth/Fact No. 3

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  • "Everyone knows the Internet is fundamentally royalty-free. Why change now?"
  • Many people do believe so, but not everyone agrees.
Without disclosure, the true state of technology is not RF, not RAND, but FUD.
W3C 

Information

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