Cracks and Mortar

http://www.w3.org/2007/Talks/1107-tpac-tbl/

Tim Berners-Lee

Extensibility, culture

Director, W3C

Welcome

• KUTGW
• Remember other groups
• Larger
• Peer
• Smaller

Design for the fractal tangle

Content Type

• a.k.a. Mime Types, Internet Media Types, ...
• Flexibility point
• Allow server to evolve independently of link source
• HTML5 proposes: ignore mime Content-type of image
• We move on slowly, but conneg allows us to do that.
• Only use it when resources are substitutable
• Operating systems should pass URI to helper application

TAG Soup

• Not the end of the world
• Frustrating
• Was insisting on the quotes a good idea?
• Documenting existing practice is fine
• Working toward clean markup is important

Validation?

• Should allow eXtensibility
• Should explain problems and motivation
• Should provide a fixed version
• Should balance its level of disapprobation
• Should validate web architecture

Browsers

• Save As -> cleaned markup
• View Source -> Cleaned markup + annotations
• View source/with errors
• Should include validators + tidy

Namespaces

• An RDF requirement
• Implemented in XML
• URI-based extensibility
• Take up space

Alternatives

• Central registry of terms - Microformats
• Works for finite set of global terms (like HTML)
• Does not work for other communities

New tags and attributes in HTML

• Validator complains
• Microformats overload classes
• ARIA etc add class micro syntax
• but ... XML was supposed to be eXtensible!
• Unknown NS tag with NS document: not a bug.
• Unknown tag with no NS -- who knows?

Canvas vs SVG

• Sigh ...

You are all here together - talk!

XML Top-down dispatch

A recursive flexibility point

• (x)HTML
• SVG
• Encryption
• MathML
• XSLT expression (template mode)

A recursive flexibility

Multiple namespaces in RDF

• The original requirement
• Successful: works
• Multiple applications blend
• Multiple sources blend (e.g. tabulator)

Should NS technology not have been used to the XML layer?

Exciting things

• Linked data - linking together the web 2 platforms
• CDF -- Open alternatives to Silverlight and AIR
• FOAF+Open ID blocking spam with the social graph, open social networks
• Web goes Mobile
• Video as first class citizen
• etc etc

Double bus architecture

Thank You

KUTGW

http://www.w3.org/2007/Talks/1107-tpac-tbl