Introducing the TAG

1. The World Wide Web Consortium

Founded by Tim Berners-Lee to sustain the value of the Web for everyone and "lead the Web to its full potential"

Hosted by MIT in US, Keio University in Japan and ERCIM in Europe

~60 employees, about half working remotely

Over 400 members: organisations and companies

Recently awarded substantial support from ISOC

Standards work carried out by Working Groups made up of member representatives and invited experts

100s existing Recommendations, dozens in progress from >50 WGs

Mostly 'horizontal' technologies

• HTML (itself, Forms, CSS)
• XML (itself, XSLT, Schema, Query, Processing Model, Linking
• Multimedia (PNG, SVG, SMIL, VoiceXML)
• Mobile (Mobile Web Initiative ('one web'), Mobile CSS, Geospatial (!))
• Semantic Web (RDF, OWL, Rules)
• Accessibility
• Internationalisation

2. The Technical Architecture Group of the W3C

Originally the Director (Tim B-L) was responsible for maintaining consistency across activities

As the Consortium grew and the scope of its activities enlarged, this task became impossible

The TAG was established eight years ago to pick up and broaden this task

• Identify and promote core principles of Web Architecture
• Look backwards at what has made the Web succeed
• And forwards to what must be done to protect that success
• While embracing as much as possible that emerges

3. TAG membership

Tim Berners-Lee ex officio

Three appointed members

• Noah Mendelsohn (retired, ex-IBM) (chair)
• Jonathan Rees (Science Commons)
• [vacant]

Five elected

• Dan Appelquist (Vodaphone, London)
• Ashok Malhotra (Oracle)
• Peter Linss (Hewlitt-Packard, San Diego)
• Henry S. Thompson (University of Edinburgh)
• Larry Masinter (Adobe, California)

Plus Yves Lafon, staff contact

Weekly 'phone conferences, four face-to-face meetings yearly

4. Architecture of the World Wide Web

A grandiose concept

• In practice an ongoing post-hoc analysis project with respect to a vast, messy, poorly delimited real-world phenomenon

A document

• The first publication from the Technical Architecture Group of the W3C (World Wide Web Consortium)
• Architecture of the World Wide Web, Volume One
• The goal of the document is to "preserve [the properties underlying the success] of the information space as the technologies evolve"
• It contains a number of "Principles, Constraints and Good Practice Notes"

5. Grandmother observations about the Web

"Global naming leads to global network effects"

• A prerequisite for citation
• A challenge for many existing schemes

"To benefit from and increase the value of the World Wide Web, agents should provide [http:] URIs as identifiers for resources"

• I.e. not just any global name, but a particular kind of global name

6. More from Grandma Webarch

It's good for the ownership of a name (URI) to be manifest in the form of that URI

• We need to know who is responsible for the name and its use

"A URI owner should not associate arbitrarily different URIs with the same resource."

"Agents do not incur obligations by retrieving a representation."

• HTTP 'GET' is side-effect free (c.f. cookies)

"A URI owner should provide representations of the resource it identifies"

7. In a nutshell

The Web works because you can

• View Source
• Follow your nose
• Write URIs on the side of a bus
• Use generic tools
• Redirect, cache and proxy

8. The TAG and the IETF

So far I've talked about how we see ourselves

• From within our own W3C space

WebArch was (mostly) squarely within W3C territory

• But many of our more recent concerns have drawn us towards IAB territory
• So it's clearly time to give some thought to demarcation

Some overlap is unavoidable

• Indeed even beneficial

But it needs to be recognised and managed

9. TAG priorities

The TAG has organised its current activities under four broad headings:

1. The future of HTML
2. Privacy
3. Web Application Architecture
4. Core Mechanisms of the Web

This list is broadly in line with the W3C's own stated priorities:

1. Powerful Web Apps
2. Data and Service Integration
3. Web of Trust
4. Television, Mobile and the Web of Devices
5. One Web for All

10. The rise and rise of port 80

HTTP, HTML and the browser have come to increasingly dominate the Internet

• FTP, NNTP and even SMTP have been supplanted
• The browser has become the universal information appliance

Tensions and problems have arisen because HTTP, HTML and the browser were not designed to be a distributed application delivery platform

• But it's manifestly too late to stop and "get it right" from first principles
• So we have to manage their ongoing re-purposing as best we can

11. New areas for Web/Internet Architecture

All but the first of the following (relatively) new webapps-related TAG issues are, it seems to us, IAB issues as well:

• Use of URIs for identifying (parts of) application state
• Rethinking privacy
• Web Security as it becomes Application Security
• Device APIs: the difficulty of distinguishing between protocol and API