W3C

• The World Wide Web Consortium (W3C):
• the neutral forum where Web Standards are developed
• The World Wide Web Consortium (W3C): the neutral forum where Web Standards are developed
• Our keywords: consensus and neutrality
• Our mission: “… to lead the Web to its full potential.”

A High Level Overview

• This presentation does not go into the technical details
• The goal is to give a feeling how technologies fit together

Some Guiding Principles at W3C

Web Technologies should be interoperable

• the Web is based on a large palette of technologies
• no technology can pretend to cover all needs on the Web
• hence the interoperability of technologies is a must!

The Web is universal and for everybody, regardless of:

• language
• user capabilities
• device used for access
• geographical location
• …

Data: XML & XML Toolkit

• XML is a key technology to ensure interoperability
• But XML, by itself, is not really useful… we need to:
  • have datatypes, validation (DTD-s, Schemas, …)
  • mix XML specifications/applications (Namespaces)
  • use hyperlinks (XLink, XBase, …)
  • compose/decompose (XInclude, Fragments, …)
  • refer to XML data content (XPath, Query, …)
  • transform (XSLT)
  • encrypt, decrypt, sign (Signature, Encryption, …)
  • interact, script (DOM, Events, …)
  • etc.
• They form the “architectural” foundation of the Web

Usage of the Web has Evolved

Data & People

• Technologies for:
  • text documents (XHTML, MathML)
  • graphics, multimedia (SVG, SMIL)
  • voice dialogs (VoiceXML)
  • interactive forms (XForms)
  • controlling presentation (CSS)
  • transmitting stylus interaction data (InkML)
  • …

What Some of Them Do…

Data & People (cont.)

• Most of them are XML applications
  • W3C has some non-XML technologies, too (WebCGM, PNG)
• Most of them are fairly mature by now, tools and implementations emerge
• The Mobile Web is strongly coming to the fore
  • most recent technologies have their “mobile” versions: XHTML Basic, SVG Tiny and Basic, SMIL Basic, XForms Basic…
  • W3C has recently launched the Mobile Web Initiative to concentrate on this area.
    • authoring guidelines, information depositories for devices, usability issues, …

New Challenges

• Integration of various formats in one document
  • example: integration of MathML, XHTML, and SVG in Amaya
  • usage of XML is a key
  • the “Compound Document Formats” work has already published its first draft
• Web Applications
  • interoperability of tools to develop client-side applications like GMail, games, auction sites, e-commerce, …
  • W3C is in the process of starting a new activity in the area

Data & Machines

• Computers co-operate through the Web
  • goal is to achieve an improved user experience
• Typical applications:
  • search engines, on-line catalogues, news services, user profiling, e-commerce,
  • shared computing resources, computational services (stock values, translations,
  • weather, …)
• Typical applications:
  • search engines, on-line catalogues, news services, user profiling, e-commerce, shared computing resources, computational services (stock values, translations, weather, …)
• Two major approaches emerge:
  • service based
  • metadata based

Data & Machines, Service Based

• Providers expose “active” services on the Web
  • documents are transferred to these services for processing
  • results may be returned as documents, too
• Defines a document oriented distributed computing model
• Call patterns can be defined for complex applications
• Remote procedure calls can also be described
  • I/O parameters transferred as a special documents
  • relies on appropriate conventions
• Area collectively known as Web Services
  • reminescent of other models, e.g., distributed objects
    • but not the same! E.g., there is no concept for object lifecycle
  • the ubiquitous Web/Internet infrastructure is a key for deployment

Data & Machines, Service Based (cont.)

• In Web Services, all major blocks are described in XML
• W3C concentrates on some of the basics of WS:
  • protocol to transfer data over the Internet (SOAP)
    • the document to transfer is itself in XML, too, but binary content can also be transferred
    • transfer may rely on HTTP, but not necessarily
  • precise addressing of each service (WS-Addressing)
  • description of the service interfaces (WSDL)
  • global view on cooperating services (WS-CDL)
    • referred to as “choreography”, based on π-calculus
  • other areas are under discussion
• Other building blocks are done elsewhere
  • these are usually on a higher level

Example: Travel Agency

Data & Machines, Metadata Based

• Metadata is added to Web resources; they describe properties of the resource
• Metadata vocabularies (ontologies) can be developed
  • makes a logical reasoning on the metadata possible, e.g.
    • “if this property is true, then that property is true…”
    • “this property is that same as that property…”
    • etc.
• Applications are based on analysing the metadata (e.g., search engines)
• This is the area of the Semantic Web “an infrastructure for reasoning on the Web”
• Main W3C Technologies in the area:
  • a unified model and textual encoding for metadata storage (RDF)
  • a language for defining ontologies (OWL)
  • query language for RDF data (SPARQL)

Data & Machines, Metadata Based (cont)

• Metadata refer to general URIs
  • one can define metadata on resources somewhere else (“cataloguing services” become feasible, for example)
  • one can combine metadata from different sources
  • the Web can be viewed as a big database with sophisticated search and retrieval facilities

Example: Adobe’s XMP

• Adobe’s tool to add RDF-based metadata to most of their file formats
  • used for more effective organization
  • supported in Adobe Creative Suite
  • support from 30+ major asset management vendors
• The tool is available for all!

WS/SW: Complementary Technologies

but, also

Examples for Potential Synergies

• Semantic Web based search engines for Web Services
  • search based on complex constraints
    • e.g., “find the most elegant Schrödinger equation solver”
• “Match-making”
  • i.e., combining various services based on their semantics

Examples for Potential Synergies (cont)

• RDF Database services with complex Queries
  • queries and query results transmitted in, e.g., SOAP
  • query facilities described in WSDL
• Ontology services
  • “provide a Web Service to make logical deductions on my behalf”
  • (e.g., on complex metadata with an ontology)
    • find and manage equivalences
    • make logical deduction of terms
    • check SW description for validity
    • etc
  • “provide a Web Service to make logical deductions on my behalf” (e.g., on complex metadata with an ontology)
    • find and manage equivalences
    • make logical deduction of terms
    • check SW description for validity
    • etc.

Convergence (at W3C and Elsewhere)

• Lots of discussions on convergence at W3C
  • a workshop on “Frameworks for Semantics in Web Services” took place in June 2005
  • the current plans are:
    • develop a core vocabulary and structure to add Semantics data to, say, a WSDL entry.
    • gather use cases, requirements, etc, on a SW based coordination of services, automatized service discovery, etc. There are submissions in the area (e.g., OWL-S, WSMO). Might lead to a more detailed work
• there are discussions on a UDDI version being expressed in RDF
• …

The Web is for Everybody!

• Regardless of language, culture, geographical location
  • the majority of Web users are not English speakers
  • it is not only an issue of character sets…
    • directions of writing, …
    • format of dates, phone numbers, ZIP codes, numbered items, …
    • different keyboard types, …
• Regardless of user capabilities
  • color or total blindness, …
  • difficulties with a keyboard, mouse (eg, RSI problems), …
  • dyslexia, cognitive or neurological difficulties, …
• Regardless of device types and capabilities
  • PC-s, phones, TV-s, PDA-s, …
  • low bandwidth, small B/W screen, no sound, no screen, …

How do we Achieve This?

• XML formats should be usable in possibly all circumstances
  • e.g., proper data structures for dates, facilities for metadata
• XML data might have to be properly annotated
  • XHTML’s alt attribute for images is a typical example
• The infrastructure should adapt itself:
  • separation of the information from the presentation
  • describe the environments and let the tools adapt
• The Semantic Web has an important role to play!
  • adding metadata to images
  • describing device capabilities
  • …

Horizontal Activities at W3C

• W3C has a number of activities to reinforce those principles
  • “horizontal” review of all W3C technologies:
    • internationalization, multimodality, accessibility, device independence, …
    • specification can be “sent back” to the drawing board if problems occur!
  • separate education and outreach activities:
    • tutorials, information for designers, quicktips, guidelines

Example: International Text

Results: Over 60 Different Technologies!

Further Information

These slides are at:

/Consortium/Offices/Presentations/Overview/

More information about W3C:

/Consortium/

Contact information:

/Consortium/Contact

Mail me:

ivan@w3.org