Content Adaptation in
the Ubiquitous Web

Vincent Quint, INRIA
<Vincent.Quint@inria.fr>

W3C Ubiquitous Web Workshop, Tokyo, 10 March 2006

Introduction

Content adaptation in the ubiquitous Web:

• Content adaptation is an important element of the Ubiquitous Web
• Focus on information resources, emphasis on multimedia information
• In the ubiquitous Web information should be usable in different contexts
• Existing resources have to be adapted to the actual context
• Web infrastructure should provide several components to enable efficient adaptation

Outline

Components for content adaptation:

• Context description
• Transformation for adaptation
• Negotiation protocols
• A distributed architecture

Context Description

Context must be described in a machine-readable manner

• CC/PP and UAProf are available -- description of device capabilities and user preferences
• DCI is in progress -- interfaces to access dynamic properties (device capabilities, configurations, user preferences, environmental conditions)
• MWI is working on device description

Adaptation

Some technologies are available for adapting contents

• CSS (format, style), ACSS (change of modality)
• Alternate content
  • switch element in SVG, SMIL
  • DISelect -- content filtering and selection
• Transformations

Transformation

In multimedia documents both structure and media objects may have to be transformed

• XSLT for structure transformation
• specific tools for media objects

Some problems with XSLT

• Validation: how to make sure that transformed documents are valid?
• Streamed data: transforming data on the fly, large documents

Negotiation Protocols

How to choose the right transformation(s) based on context description?

• compromise: available transformations and constraints from the context
• negotiation to find the best compromise

HTTP 1.1 offers limited negotiation (choosing among the available versions)

More flexibility is needed to adapt documents dynamically

Architecture

Several components are required:

• Context description
• Negotiation based on context
• Transformation of content and structure

Include these components in all clients and servers?

A Distributed Architecture

Summary

Content adaptation is a key issue for the ubiquitous Web

It requires

• Context description:
  on-going effort at W3C
• Transformation:
  further research is needed
• Negotiation protocols:
  lack of standardization effort