Transcript [Powerpoint 97 Format]

Advances In Web
Technologies
1
Brian Kelly
UK Web Focus
UKOLN
University of Bath
[email protected]
http://www.ukoln.ac.uk/
Contents
• About UK Web Focus
• End user developments:
• browsing
• searching
Aim of this talk:
• To outline major developments
on the web
• To explain why they are important
• To identify possible barriers to
their use
• Developments for information providers
• document management
• metadata
• structured documentation
• Technologies
• HTML
• HTTP
• Java
• Will it Take Off In Our Community?
2
UK Web Focus
UK Web Focus:
• National web coordination post for UK HE community
• Based at UKOLN, University of Bath
• Responsibilities include:
– Technology watch
– Information dissemination in variety of ways:
– Workshops (national, regional)
– Presentations at conferences and seminars
– Online
– Coordination activities
– Representing JISC on W3C
• Brian Kelly appointed on 1st November 1996
3
– Involved with web since January 1993
– Previously worked at University of Newcastle, Leeds,
Liverpool, and Loughborough
Web Visualisation
http://www.dynamicdiagrams.com/
Visualisation of a web site
to aid end user navigation
Why: To make navigation
easier for end users
To provide tailorable
views (e.g. only show
"personal home pages")
Barriers: Lack of
standards. Proprietary,
licensed software.
See also WebCutter at
http://www6.nttlabs.com/
How: Web Collections
HyperNews/get/PAPER40.html
Familiarisation: MAPA,
NetObjects Fusion
4
Light-weight Browsers
Light-weight browsers
such as Opera and
Lynx are available
5
Why: To support low
spec PCs (e.g. 386
SX with 8MB and Win
3.1)
Barriers: Costs ($10 for
100-500 copies), use
of proprietary HTML
How: Opera, Lynx,
Bobcat
Familiarisation: Free
evaluation
http://opera.nta.no/
http://www.operasoftware.
com/
http://lynx.browser.org/
http://www.fdisk.com/
doslynx/
Better Searching (1)
Why: Time wasted in
searching
Barriers: Lack of
metadata standards.
Lack of tools
How: Dublin Core
Familiarisation: Read
UKOLN resources at
http://www.
ukoln.ac.uk/
metadata/
Take part in pilot
6
Better Searching (2)
Application of
heuristic techniques
in searching
Why: Time wasted in
searching
Barriers: Lack of
organisational
guidelines
How: Heuristics.
Consistency in URLs
across institution
Familiarisation: Ahoy!
7
http://ahoy.cs.
washington.edu:6060/
A Manageable Web (1)
Use of metadata for site
management
Why: Site metadata on
authoring tools,
authoring methods,
document types, ..
Barriers: Lack of
standards
How: Dublin Core, PICS,
XML,...
Familiarisation: UKOLN
metadata work,
UCISA-TLIG work
8
Metadata to assist with
following requests:
• Find all pages
created using
Internet Assistant v1
• Find all pages which
use Jscript
• Find pages where
author = {find author
from departed-staff}
Development of a
Metadata Architecture
Metadata - the missing
architectural component
from the initial
implementation
of the web
Addressing
URL
Transport Data format
HTTP
HTML
9
Metadata Components
PICS, Digital Signatures, Transparent Content
Negotiation, resource discovery, website administration
are all related to metadata
Example
Imagine you make
your University
prospectus available
on the web.
What metadata may
be required?
10
Use Of Metadata
PICS Resource accessible to users in
Middle East, which ban unrated sites
DSig Description of course is a legally
binding agreement
TCN Resource can transparently be
accessed in HTML or PDF format
Web Collections
Print resource as single document
Resource Discovery
Search for Bath prospectus finds it
Website Administration
Use of review-by to find out-ofdate material
A Manageable Web (2)
Use of server side
management techniques
Why: Single copy to
minimise maintenance
Barriers: Performance,
cost of software, Unix
How: Server side
includes,
Familiarisation: MS
Active Server Pages,
Netscape SuiteTools,
PHP/FI, ...
11
<If useragent=netscape1.1 then
else if useragent= …>
<P>This resource is copyright ...
Adding code / text to static
HTML resource:
• complex
• difficult to maintain
<#If useragent=netscape1.1 then
else if useragent= …>
<#include copyright-1.txt>
Server side management
tools:
• HTML resource clean
• easier to maintain
<SCRIPT LANGUAGE="JavaScript">
<!-- Hide this from JavaScript-challenged browsers
var FirstSlide = 1;var LastSlide = 17; var CurrentSlide = FirstSlide;var ImageWidth = 708 - 8;
var ImageHeight = 520; var CurImageWidth = ImageWidth; var CurImageHeight = ImageHeight;
/* This function concerts numbers to strings
*/ <HTML><BODY >
<A HREF="JavaScript:parent.
function CvtNtoS(iNum)
ItemClicked(1, 0)"> An Introduction to
{return ("" + iNum);}
/* This function prefixes strings with the correct # of 0's */Metadata </A><BR>
<A HREF="JavaScript:parent.
function ZeroFill(iNum, iDigits)
ItemClicked(2, 0)"> UK Web Focus
{ var sNum = CvtNtoS(iNum);
</A><BR><A HREF="JavaScript:
while (sNum.length < iDigits)
parent.ItemClicked(3, 0)"> Early Days
sNum = "0" + sNum;
of the Web (1) </A><br>
return sNum;}
HTML><BODY >
/* this function handles the setting the navigation buttons.
<base target="_top">
The name of navigation control is used here so change it if it is renamed
*/
<A
HREF="JavaScript:
function ItemClicked(iIndex, iNoteOnly)
parent.OutlineExpand(0)"><IMG
{var sIndex = ZeroFill(iIndex, 3);
SRC="collapse.gif" BORDER=0
var sNoteHref = "note" + sIndex + ".htm";
ALT="Collapse"></A>
var sSlideImage = "img" + sIndex + ".htm";
<A HREF="JavaScript:
if (!iNoteOnly)
// not active X, update image and nav btns
parent.OutlineExpand(1)"><IMG
frames["SlideImage"].location.href = sSlideImage;
SRC="expand.gif" BORDER=0
frames["Notes"].location.href = sNoteHref;
ALT="Expand"></A>
CurrentSlide = iIndex;}
<STRONG>Demise of Tags</STRONG>
Demise of text editors
for authoring
Why: HTML will be too
complex
Barriers: Inertia. Too
many tools!
How: Recommendations
on authoring tools
Familiarisation: Front
Page, Netobjects
Fusion, ...
12
HTML Developments
13
End user control
over layout, better
printing, ...
Why: Increased
functionality
Barriers: Lack of
standards
How: CSS, HTML
4.0 (Cougar)
Familiarisation: IE
4, Netscape 4,
HTML 4.0
proposal, CSS 2
proposal
HTML 4.0 and Related Work
• Forms:
Improved forms
• Printing:
Better control over printing
• Layout:
Absolute positioning of HTML
elements, layering, etc.
• Scripting:
Standard mechanisms for scripting.
• Document Object Model (DOM):
APIs (application program
interface) for HTML/CSS elements.
Provides a programming interface
for HTML (hooks for Javascript,
etc.)
The SGML / HTML
philosophy is to use
HTML to define the
document structure
Netscape / Microsoft
wars have broken this
Companies are now
supporting CSS:
14
• Ease of maintenance
• Richer functionality
(e.g. filter effects as in
Powerpoint)
• Network friendly
• Accessibility
Increasing Use Of Java
15
Expect to see increasing
use of Java:
Why: Provide extra
functionality on client;
Minimise support load
for desktop applications
Barriers: Performance
concerns (real and
imaginary - cf XMosaic)
How: Standard web
browser
Z39.50 clients are being
Familiarisation:
http://www.gamelan developed using Java
.com/
An Accessible Web
Web resources accessible Technologies
to people with disabilities
• Style sheets:
Why: Equality. Spinoffs
control over appearance
for "temporarily ableneeded by designers, but
with end user ability to
bodied persons"
change appearance (not
Barriers: Lack of
achievable with images)
standards, lack of
• Aural style sheets:
awareness, misuse of
e.g. <STRONG> rendered
HTML
as LOUD voice, or pause
before phrase,
How: WAI, Institutional
<DT>, <DD> rendered using
policies
male / female voices,
Familiarisation: WAI
columns in tables using left
pages
and right stereo channels
16
A Customisable Web
End user choice of preferred
formats (HTML or PDF, GIF
or PNG), features (frames or
tables), languages, etc.
Why: Choice for the end
user, deployment of new
features
Barriers: Lack of standards,
misuse of HTML
How: TCN, Cookies
Familiarisation:
http://tips.iworld.com/
17
Replace this with use of
cookies or transparent
content negotiation
Maths
Mathematical formulae
on the web.
Why: Needed by
scientists, images of
formulae are slow and
have no semantics
Barriers: Lack of
standards
How: MML, XML, Java,
ActiveX
Familiarisation:
http://www.w3.org/
MarkUp/Math/
18
A Quicker Web
More effective use of
scarce bandwidth
Why: The web is too slow!
Barriers: Limitations of
protocols (HTML, HTTP)
How: Caching, HTTP/1.1,
HTTP/NG, Education,
Charging!
Familiarisation:
Monitoring web pages,
Internet magazines,
attending workshops
19
Technologies
• Caching:
Essential!
• HTTP/1.1:
New protocol is more cacheaware, and avoids problems
(e.g. stale information) which
have occurred in the past
• HTTP/NG:
Proposal for new protocol
• Style sheets:
Avoids need for large images
for design effects
• Scripting Languages / Java:
Exploit processing power at
client
Collaborative Tools
Use of collaborative and
conferencing web tools.
Why: Provide rich
collaborative tools
Barriers: Lack of locking,
notification systems,
HTML deficiencies
How: WebDAV work,
Cougar
Familiarisation: Amaya,
http://union.ncsa.
uiuc.edu/HyperNews/
get/hypernews.html
20
Structured Documentation
Store web resources in a
rich structured open
master format
Why: To overcome HTML
deficiencies
Barriers: Lack of
standards. HTML
provides little structure
How: XML
Familiarisation:
Jumbo browser
See also
http://www.textuality.com/xml/
21
Richer Hyperlinking
Richer forms of hyperlinking
Why: Increased functionality
Barriers: Lack of standards
How: XML, Javascript
Familiarisation:
SoftQuad HiP,
http://www.w3.org/
XML/
Reference
Tutorial
See further instructions
22
English
French
XML-Linking
Multi-way links
Link destination:
• Replaces existing
document
• Included inline in
document
• Displayed in new
window
Resolve link at:
• document load
• user action
Push Technologies
Use of push
technologies
Why: Push information,
teaching and learning
services to end users
Barriers: Lack of
standards, bandwidth
concerns
How: CDF, ...
Familiarisation:
Pointcast
IE 4, Netscape
23
Will It Take Off In UK HE?
Barriers to use of new technologies:
•
•
•
•
Lack of knowledge
Lack of tools
Inertia
Concerns over costs
Solutions:
• Education, information, discussion, …
• UCISA-SG WebTools group
Commercial pressures
• Enthusiasts
• Monitoring usage
24
UKOLN's WebWatch Project
WebWatch:
• 1 year post funded by British Library (BLRIC)
• Will develop set of robot tools for analysing UK
web resources:
– Usage of emerging web technologies, such as HTML 4,
style sheets, Java, metadata, XML, etc.
– Usage of file formats (e.g. PDF, Shockwave, …)
– Web page profiles (typical nos. of links, images, size, etc)
– ...
• Analysis of log files (e.g. user agents)
• Results to be made available to various
communities (institutions, national bodies, etc.)
• Feedback on project welcomed
25
Conclusions
• The web is still developing rapidly
• Conformance to standards is important
• Institutions will have to continually monitor new
developments (regional workshops, seminars?)
• The deployment of new technologies in a timely
manner is a challenge (need for workshops, case
studies?)
• There is a danger that the costs will increase
when exploiting new developments
• There is a need to monitor developments and to
advise the community
26