WWW 6 Trip Report
Report on the Sixth International
WWW Conference held in Santa
Clara on April 7-11, 1997
Brian Kelly
UK Web Focus
UKOLN
University of Bath
BA2 7AY
1
Contents
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B.Kelly@ukoln.ac.uk
http://www.ukoln.ac.uk/ •
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About WWW 6
W3C Session - HTML
Microsoft IE 4.0
W3C Session - HTTP
Web Site Mapping Workshop
XML Tutorial
Technical Papers
Plenary and Panel Sessions
UK Web Focus
UK Web Focus:
• National Web coordination post
• Responsibilities include:
– Technology watch
– Information dissemination
– Coordination
– Representing JISC on W3C
• Based at UKOLN, University of Bath
• Brian Kelly appointed on 1st Nov 1996
• Formerly worked at Netskills (Newcastle University)
and universities of Leeds, Liverpool and
Loughborough
2
About WWW 6
WWW 6:
• Held at the Santa Clara Convention Centre
• Workshops and tutorial sessions on
Monday 7th April
• Technical papers from 8-10th April
• Developer's Day and History Day on 11th
April
• Various other BOFs and meeting (including
Web Accessibility Initiative day)
• About 1,800 participants (down on
previous years)
3
Before the Conference
• Conference details
including online booking
available on Web -
http://ice.www6conf.org/
http://www6conf.org/
• Online conference (ICE)
available for delegates
before, during and after
conference
• Conference proceedings
available online
http://proceedings
.www6conf.org/
4
Accessibility
Accessibility was
conference theme
Web Accessibility Initiative:
• About 80 participants
• WAI approval
Issues
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• Accessibility is important
• WAI will address:
protocols, software
developers, information
providers and end users
http://www.lbc.co.uk/
• Need for university /
departmental / project policy?
Accessibility
Comments made by Peter Bosher (RNIB):
6
• Poorly designed navigation (when you follow
several links, and then get back to where you
started) is a particular problem for the blind
who don't have the visual clues that the
sighted have
• When navigating the Hotwired site his
browser said "link link link link image image
image without caption"
• Tables are difficult to process by speech
browsers
• Painstakingly competing a form and then
getting an error message because the form
was browser specific is annoying
Further Information
Further information on the Web Accessibility
Initiative, and on general accessibility
resources is available at:
http://www.w3.org/pub/WWW/Disabilities/
http://weber.u.washington.edu/~doit/
Other/design.html
http://www.igs.net/~starling/acces.htm
http://trace.wisc.edu/
http://access.adobe.com/
http://cs.cornell.edu/home/raman/
7
W3C Session
HTML Developments
Cougar:
• Code name for next version of HTML
• Needed as "forces driving evolution of HTML are
threatening media independence"
• First draft available summer 97
• Some parts already released:
WD-htmllink
WD-script
WD-frames
WD-forms
WD-object
WD-entities
WD-fileupload
(WD-printing, WD-positioning)
• See http://www.w3.org/pub/WWW/
MarkUp/Cougar/
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Day 1 - 2 pm
W3C Session
WD-htmllink
WD-htmllink
• Hypertext links in HTML.
• Defines link relationships (e.g. <LINK REL=Next>
could be used to facilitate printing in a single
document split into several files)
• Related to Style Sheet work
<LINK REL=Stylesheet MEDIA=print
HREF=ukoln-print.css>
• Define TITLE attribute for hints for accessibility e.g.
<A HREF="welcome.html" TITLE="The
Welcome page for ACME Ltd">text</A>
In this example a browser could display the text in,
say, a pop-up window.
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Day 1 - 2 pm
W3C Session
WD-htmllink
WD-htmllink (continued)
• Defines uses of META tag (e.g. for use with
PICS)
• Define language(s) for documents
• Define pages which can be indexed by robots
<META NAME="ROBOTS"
CONTENT="NOINDEX, NOFOLLOW">
prohibits robots from indexing and
following links
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Day 1 - 2 pm
W3C Session
WD-script
WD-script
• Client-side Scripting and HTML
• Defines mechanism for embedding scripting
languages in HTML:
<SCRIPT type="text/javascript">
document.write ("<EM>This will work</EM>")
</SCRIPT>
• <SCRIPT SRC="url"> used for external scripts
• Default script language can be defined:
<META HTTP-EQUIV="Content-ScriptType" CONTENT="text/tcl">
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Day 1 - 2 pm
W3C Session
WD-frames
WD-frames
• Defines existing usage of FRAME tag
• Includes IFRAME proposal for inclusion of frames
inline in body of HTML documents (FRAME tag
replaces BODY tag):
<BODY>
<P>This document contains an inline frame
<IFRAME src="foo.html" width=400 height=500>
that unfortunately your user agent doesn't
support. Alternatively you can get the
related document <A href="foo.html">here
</A>.</IFRAME> That's all folks!
</BODY>
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• Initial release of FRAMES caused problems,and
there are still accessibility concerns
Day 1 - 2 pm
W3C Session
CSS
The CSS1 (Cascading Style Sheet) spec:
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•
•
•
Replaces all HTML extensions
Can replace most uses of tables
Provides floating text elements
Provides control over background
WD-style
• Defines relationships between HTML document
and stylesheet
• Cascading style sheets can be defined by:
<LINK REL=stylesheet HREF="corporate.css">
<LINK REL=stylesheet HREF="techreport.css">
• Can define alternate style sheets for media types:
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<LINK REL=stylesheet MEDIA=screen …>
Day 1 - 2.45pm
W3C Session
CSS - The Next Wave
In next version of CSS:
• Multiple media (using @media)
• Improved printing support (headers, footers,
margins, etc.) See WD-printing
• Better control over positioning (e.g. out-of-flow
elements, navigational bars, layering) See WDpositioning
• Better font control (mixed fonts - e.g. helvetica and
cyrillic for, say, language dictionaries)
• Aural cascading style sheets. See WD-acss For
visually impaired an incar use, industrial and
medical systems, entertainment, illiterate:
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– <STRONG> rendered as loud voice, pause-before
– Left column in table spoken in left speaker Day 1 - 2.45 pm
W3C Session
CSS Questions
Q How closely matched are the CSS and XML?
A They are a good match
Q Features such as side bars (e.g. <P CLASS=side>)
are likely to be widely used. Should such attributes
be registered?
A It's likely that a set of standard style sheet definitions
will be released, and they'll be widely used
Q Will CSS held to reduce network bandwidth?
A Yes, see
http://www.w3.org/pub/WWW/Protocols/
NL-PerfNote.html
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Q What about headers and footers?
A In next release
Day 1 - 2.45pm
W3C Session
HTML Math
The HTML Math spec:
• Released in May 97 - see
http://www.w3.org/TR/WD-math
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• Core standard covering presentation and markup
• Will contain 20 presentation tags with 40 attributes
• Will contain 50 content tags (roughly equivalent to
functions on scientific calculator)
• Initially implemented using embedded elements
(ActiveX, Java) enabling 3rd parties to develop
rendering tools (won't need to wait for Netscape /
Microsoft)
• Software will be available in June 97
• Full implementation requires better browser APIs (e.g.
DOM)
Day 1 - 2 pm
W3C Session
Dynamic HTML
• Based on work of the Document Object Model
(DOM) working group
• Provides an API (applications programming
interface) for HTML page structure and style
• Microsoft's Internet Explorer 4.0 implements
many features of Dynamic HTML
• See:
– http://www.microsoft.com/gallery/
files/html/default.htm
– http://www.microsoft.com/workshop/
prog/aplatfrm/dynhtml-f.htm
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Day 1 - 2 pm
Microsoft IE 4.0
Presentation in the Industrial Presentations track on
Internet Explorer's implementation of Dynamic HTML
HTML is limited:
• Animation using animated GIFs is limited
• Can't position or layer elements
• The web is slow - interaction with server needed
Dynamic HTML:
• Based on emerging W3C proposals
• Covers:
– Dynamic styles and dynamic contents
– CSS positioning
– Data binding
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Day 2 - 4 pm
Microsoft IE 4.0
Dynamic HTML
• Positioning control (in X,
Y and Z planes)
• Position can be changed
at run time (e.g. on
mouseOver event)
Dynamic Content
The Document Object Model (DOM) can be used to
change the content at runtime:
function change() "new header"
...
<H1 id=foo onclick=change()>Old header</H1>
For example a table of contents could be built
dynamically
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Day 2 - 4 pm
Microsoft IE 4.0
Dynamic Style Sheets
CSS properties can be changed at run time:
<H1 onMouseOver {colour: red;}
onMouseOut {color=yellow}>
A more elegant way is to store the Javascript
code in the document HEAD (or externally)
CSS Positioning
Elements can be positioned absolutely or relative to
each other
<IMG SRC="smiley.gif" : top: 25% ; zindex=1>
<DIV zindex=2>Text on top of image</DIV>
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Text on top of image
Day 2 - 4 pm
Microsoft IE 4.0
Data Binding
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Currently data binding
(merged data from
database with HTML
code) is done on the
server
Data binding proposal
enables it to be done on
the client so that, for
example, the output from
a search engine can be
resorted on the client)
But will this be in
Cougar?
http://www.microsoft.
com/gallery/files/
html/repeat.htm
Day 2 - 4 pm
Microsoft IE 4.0
Dynamic HTML
Multimedia Effects
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Uses IE4 control to provide
multimedia effects
Removes need for animated
GIF
Variety of effects available:
• Transitions, filters,
structured graphics,
sequencing
How will Powerpoint be
• sprite control (scripted
marketed if this is
animated GIFs)
possible in HTML?
• Example - e rotating in 3D
Day 2 - 4 pm
Microsoft IE 4.0
Document Object Model (DOM)
• DOM enables every HTML element to be
processed as an object (i.e. DOM is an API for
accessing HTML elements)
• DOM is not a
set of tags or a
new language
(it is language
independent)
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Day 2 - 4 pm
Netscape
Netscape have also expressed support for Cougar
See
• http://www.netscape.
com/focus3/comprod/
columns/intranet/
open_standards.html
• http://www.netscape.
com/flash1/comprod/
products/
communicator/
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Cougar and Browser Issues
Standards
• IE 4.0 conforms to HTML 3.2 and CSS1, and
implements new W3C drafts (e.g. DOM, forms)
• Netscape have also expressed commitment to
Cougar
• Javascript is being standardised by ECMA
Support for legacy browsers?
• Don't use new features
• New features degrade gracefully
• New features won't work (e.g. Tetris example 10K HTML file, which used no ActiveX controls)
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Day 2 - 4 pm
Support for Multiple Browsers
How do we deploy new features when there are
many different versions and many browsers to
support?
• Offer choice at client:
Click here if you have IE 4 or Netscape 4
otherwise click here
Maintenance of resources can be done manually
or using site management tool
• Offer choice at server:
if useragent=IE4.0 then serve index.dom.html
else serve index.html
• Various toolkits can provide this (Microsoft Active
Server Pages, Netscape Suitespot, PHP/FI)
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Developer's Day - HTTP
Transparent Content Negotiation (TCN)
• IETF draft
• Enables:
– Deployment of new data formats and tags
– Tailoring of content for new platforms
– Internationalisation
• See ftp://ftp.ietf.org/internet-drafts
/draft-ietf-http-negotiation-01.txt
• TCN spec server sends list of variants:
<IMG SRC="logo">
HTML source
{logo.gif
{logo.png
type image.png}
type image.png}
Variant list sent by server
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Day 4 - 9 am
Developer's Day - HTTP
Feature Negotiation
• IETF draft
• Part of TCN, addressing extensibility
• No more "Click here from frames, here for
tables" buttons
• Universal agreement on new features not
needed
• See ftp://ftp.ietf.org/internetdrafts/draft-ietf-http-featurereg-00.txt
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Day 4 - 9 am
Web Site Mapping Workshop
Half day workshops on web collections:
• Defining relationships between groups of related
documents
• Useful for:
– printing
– off-line browsing
– indexing
• Presentations on:
– Protocols (Web Collections, MCF, Dublin Core)
– Applications (HotSauce, WebCutter,
WebMapper)
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Day 0 - 9 am
Web Visualisation
http://dynamicdiagrams.com/
Various proprietary ways
of visualising web sites
are available (e.g. MAPA,
WebCutter)
Need a standard
for defining
relationships
between web pages,
to provide application
independence
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http://www6.nttlabs.com/HyperNews/
get/PAPER40.html
Day 0 - 9 am
Conclusions
The Web Site Mapping workshop agreed:
• Split protocol into three:
1 Metadata Model
2 File Format Syntax
3 Metadata Manipulation Language
• Further discussions needed on:
– Is a new query language is needed (e.g. SQL,
HyTime Query Language)
– Do we need a metadata query language or a
general document query language
– A list of common site mapping operations
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• XML is likely to be the preferred syntax
• Web Collections spec to be updated http://www.w3.org/pub/WWW/TR/
NOTE-XMLsubmit.html
Day 0 - 9 am
Metadata Architecture
Much work in progress in developing a
metadata architecture for the web
Addressing
URL
Transport Data format
HTTP
HTML
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XML Tutorial
XML:
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Extensible markup language
An SGML-lite designed for the Internet
Developed by the SGML community
Tools being developed by SGML tool vendors
Microsoft involvement
Two XML draft specs:
English
– XML
French
– XML-link A richer form of linking
• Stricter than HTML (to reduce client processing):
– Attribute quoting <IMG SRC="logo.gif">
– End tags needed <P>A paragraph</P>
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Day 0 - 2 pm
What's It Look Like?
What does an XML document look like?
<?XML VERSION="1.0" RMD="ALL" ENCODING="UTF-8"?>
<!doctype titlepage system "typo.dtd"
[<!entity % active.links "INCLUDE">]>
More complex XML
<titlepage>
document with DTD
<whitespace type="vertical" amount="36"/>
specified
<title font="Baskerville" size="24/30"
alignment="centered">Hello, world!</title>
<whitespace type="vertical" amount="12"/>
<!--* In some copies the following decoration is
hand-colored, presumably by the author *-->
<image location="http://www.foo.bar/fleuron.eps" Simple XML document
type="URL" alignment="centered"/>
<?XML VERSION="1.0" RMD="NONE"?>
<whitespace type="vertical" amount="24"/>
<conversation>
<author font="Baskerville" size="18/22"
style="italic">
Munde Salutem</author>
<greeting>Hello, world!</greeting>
</titlepage>
<response>Stop the planet,
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I want to get off!</response>
</conversation>
The Jumbo XML Browser
Jumbo is an XML
browser written in
Java.
It was developed to
view CML
(Chemical Markup
Language)
resources.
It can view other http://www.venus.co.uk/
XML applications. omf/cml/download.html
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CDF
XML can be used to define:
• Document structure
• Structure for metadata
• Structure for applications
CDF (Channel Definition Format) is:
• An XML application
• A proposed standard for push
technology
• Developed by Microsoft and
implemented in IE4
• See http://www.w3.org/
TR/NOTE-CDFsubmit.html
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Further Information on XML
For further information see:
http://www.textuality.com/xml/
http://www.w3.org/MarkUp/SGML/
Activity
http://sunsite.unc.edu/pub/suninfo/standards/xml/why/xmlapps.htm
http://www.ucc.ie/xml
http://www.webreview.com/97/05/16/
feature/
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Technical Paper
Extending HTML in a
Principled Way with Displets
This paper describes a Java solution to adding
new tags (charts, links, maths, etc.) to HTML.
<TAG NAME=CHART ..
SRC=chart.class>…</TAG>
<CHART TYPE=BAR>
<TABLE>
<TH> Smith<TR><TH>125…
</TABLE>
</CHART>
HTML source
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Jan
Jan
Smith 125
Green 137
Apr
Apr
257
140
Jul
Oct
Jul
327
110
Oct
250
160
HTML output
Day 1 - 11am
Extending HTML in a
Principled Way with Displets
Other extensions:
Multi-way links
Graphs
Issues:
How does this fit in with XML?
How does this fit in with the HTML Math work, which
proposes using Java to display Maths output?
Further Information:
http://proceedings.www6conf.org/
HyperNews/get/PAPER155.html
http://pegasus.rutgers.edu/
~chchiu/displets.html
39
Towards a Multimedia World-Wide Web
Information Retrieval Engine
Paper that integrates
searching for text with
searching for images.
• Search for "baseball
player"
• Select one of the images
retrieved, and search for
others similar to this one
• Give schematic drawing
(as shown)
• Provide 3D visualisation of
search results using VRML
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Find an image that
looks like this will find
Mickey Mouse from
the Disney Web site
Day 1 - 4 pm
Towards a Multimedia World-Wide
Web Information Retrieval Engine
The software is called
AMORE.
Prototype available at
http://www.ccrl.
neclab.com/amore/
See
http://www6.nttlabs.
com/HyperNews/
get/PAPER3.html
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Day 1 - 4 pm
Dynamic Reference Sifting:
A Case Study
Described Ahoy! - a
Web application used
for finding personal
home pages based
on recognition of
likely hits from
directory naming
conventions.
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See http://www6.nttlabs.com/
HyperNews/get/PAPER39.html and
http://www.cs.washington.edu/
research/ahoy
Day 1 - 4 pm
Parasite: Mining Structural
Information on the Web
Based on heuristic assumptions including:
Hypertext Linking
• A linked page is likely to be on the same topic as
the original page (esp. for Yahoo type resources)
Directory Structure
• A URL containing a directory below a personal
home page (PHP) is likely to be authored by the
person identified in the PHP
Page Structure
• Links "near" each other on a page are likely to
have similar topics
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Day 1 - 4 pm
Parasite: Mining Structural
Information on the Web
Used these assumptions to propose
applications for finding:
• moved pages
• related pages
• people
Comments
• Brute strength approach
• This and preceding paper (on Ahoy!) show
importance of directory naming conventions
(directory names provide metadata - what can we
guess from the URL
www.cs.acme.edu/staff/jsmith)
44
Day 1 - 4 pm
WebCutter: A System for Dynamic
and Tailorable Site Mapping
Paper on IBM/Lotus
product for website
visualisation
• Implemented in Java
• Map generated on
the fly
• Map can be edited
by end user (to
define user's view of
web site)
http://www6.nttlabs.com/HyperNews/
get/PAPER40.html
45
Day 3 - 2 pm
WebQuery
Paper on various
visualisation
techniques for
searching.
Based on
structural
information to
find "hot spots"
http://www6.nttlabs.com/HyperNews/
get/PAPER96.html
46
Day 3 - 2 pm
Transforming Command-Line Driven
Systems to Web Applications
This paper described work
which used Java to
provide access to a legacy
command line application
(a monolithic Fortran 77
program) on the Web:
• Input to application
via Java form
• Output in Java
applet window
http://www6.nttlabs.com
• Commercial product /HyperNews/get/PAPER41.
available soon
html
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Day 3 - 2 pm
Responsive Interaction for a Large Web
Application The Meteor Shower Architecture in
the WebWriter II Editor
An HTML
authoring tool
with server and
client side
processing.
Makes use of
frames.
Uses <BLINK> to
define flashing
cursor
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http://www6.nttlabs.com/
HyperNews/get/PAPER86.html
Day 3 - 2 pm
Seamless Integration of
Interactive Forms into the Web
This paper described
limitations of existing
forms on the Web and
described how Dynamic
Forms would overcome
these limitations.
Dynamic Forms is based
on Java.
But what about W3C
work on HTML (new
DOM and Forms
http://www6.nttlabs.com/
specs)?
49
HyperNews/get/PAPER83.html
Plenary Talk
All Authored Works Online: A Global
Infrastructure for Universal Access to
Information
Raj Reddy, Dean of the School of Computer
Science at Carnegie Mellon spoke on the Universal
Library project - when "All Authored Works of the
Human Race will be available to anyone in the world
instantaneously".
His talk is available at
http://www.ul.cs.cmu.edu/rr/aaw/
aaw.html
50
Web Design Panel Session
Good Web Design Panel Session
• A very popular session on Web design
• Panelists included Jakob Neilson (Sun),
David Seigel (a leading web designer and
author of the 1 bit clear GIF used to provide
spacing), Cathy Gill (HTML Writer's Guild)
and others
• Strong disagreements between the design
community (David Seigel) and the
structuralist community (Jakon Neilson)
51
What is Good Web Design?
What is Good Design?
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• No frames - Jakob Neilson's response (see his
paper on 10 top mistakes in web design)
• The design must be related to a user's tasks
• A well-designed site downloads quickly
• A good design doesn't break browsers
• No gratuitous backgrounds or animation
• Should be internally consistent
• Should be externally consistent in use of navigation
(Jakob Neilson's comments on need for standard
navigational aids such as not changing colours of
hypertext links)
• Variety in navigational aids (David Siegel's
response)
Bad Web Design?
There was much
disagreement over the
Seigel "hack" illustrated
53
• Image on the next page
stored in a 1 pixel by 1 pixel
• The image is downloaded
while main image is being
examined
• Moving to the next image it
appears to load quickly
• "Neat trick" - David Seigel
• "Hack", "future maintenance
problems", "no semantics"
image4.gif
<IMG SRC=image5.gif
height=1 width=1>
Other Papers
The Proceedings contains papers on:
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• Beyond HTML
• Multidimensional Web Search
• Searching Heterogeneous
Sources
• Strategies for Resource
Location
• Learning User Preferences
• Usability Issues
• Counting on the Web
• Site Mapping and Syntactic
Analysis
• Information Access
• Automatic Interface
Generation
•
•
•
•
•
•
•
•
•
Database Query Techniques
Caching
Embedded Systems
Highly Configurable Web
Services
Distributed Servers
Accessibility Using Audio
Real Time Video
Real Time Audio
Security and Payment
Conclusions
• The hit of the conference was XML
• Java was the hit two years ago - now it's
accepted as the language of the Web
• W3C are facilitating developments of web
protocols
• Closed nature of W3C standardisation
creates uncertainty but seems needed
following problems with over standardisation
(e.g. HTML 3.0)
55
Challenges
The rapid development of the web poses
various challenges for the community:
•
•
•
•
Deploying new facilities in a timely manner
Choosing the winners
Spotting the winners
Minimising future web re-engineering
How can the community address these
challenges:
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•
•
•
•
Institutionally
Regionally
Nationally
Internationally