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Web Developments For The JANET Community. Brian Kelly UK Web Focus UKOLN University of Bath, Bath, BA2 7AY [email protected] http://www.ukoln.ac.uk/. UK Web Focus. UK Web Focus: National web coordination post for UK HE community Based at UKOLN, University of Bath - PowerPoint PPT Presentation
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Web Developments For The JANET Community
Brian Kelly
UK Web Focus
UKOLN
University of Bath, Bath, BA2 7AY
http://www.ukoln.ac.uk/
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UK Web FocusUK 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– Involved with web since January 1993– Previously worked at University of Newcastle, Leeds,
Liverpool, and Loughborough
Voting on new standardsVoting on new activitiesSeeking involvement from UK HE
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W3C Activities• Public charters & workplans• Closed discussion groups, draft
papers• Participation encouraged• See http://www.w3.org/
User Interface
• HTML• Style Sheets• Document Object
Model• Math• Graphics & 3D• Internationalisation• Fonts• Amaya
Technology & Society
• WAI• Digital Signatures• Electronic Commerce• Metadata• PICS• IPR• Privacy &
Preferences• Security
Architecture
• HTTP• Addressing (URLs)• Object Technology• Synchronised
Multimedia• XML• Jigsaw
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HTML DevelopmentsEnd 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.)
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.)
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The SGML / HTML philosophy is to use HTML to define the document structure
Netscape / Microsoft wars have broken this
Companies are now supporting CSS:
• Ease of maintenance
• Richer functionality (e.g. filter effects as in Powerpoint)
• Network friendly
• Accessibility
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Increasing Use Of JavaExpect 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
Familiarisation: http://www.gamelan.com/
Z39.50 clients are being developed using Java
Z39.50 clients are being developed using Java
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Metadata Components
PICS, Digital Signatures, Transparent Content Negotiation, resource discovery, website administration are all related to metadata
ExampleImagine you make your University prospectus available on the web.
What metadata may be required?
Use Of MetadataPICS Resource accessible to users in
Middle East, which ban unrated sitesDSig Description of course is a legally
binding agreementTCN Resource can transparently be
accessed in HTML or PDF formatWeb Collections
Print resource as single documentResource Discovery
Search for Bath prospectus finds itWebsite Administration
Use of review-by to find out-of-date material
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Development of a Metadata Architecture
Metadata - the missing architectural component from the initial implementation of the web
Metadata
PICS, TCN,
MCF, DSig,
RDF, DC,...
AddressingURL
Data formatHTML
TransportHTTP
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A Quicker Web
More effective use of scarce bandwidthWhy: 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
Technologies
• Caching: Essential!
• HTTP/1.1:New protocol is more cache-aware, 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
Technologies
• Caching: Essential!
• HTTP/1.1:New protocol is more cache-aware, 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
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Caching
UK early pioneer in web caching:• HENSA cache launched in 1994
• Paper at WWW 1 presented at CERN (May 94)
• Cache migrated from Lagoon CERN Netscape
• Paper at WWW 5 presented in Paris (May 96)
JANET WWW cache:• Launched on Aug 1997
• Hosted at Manchester & Loughborough
• Service and development arms
• See http://wwwcache.ja.net/ and http://www.net.loughborough.ac.uk/caching/CacheNow/
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A Quicker Web
More effective use of scarce bandwidthWhy: 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
Technologies
• Caching: Essential!
• HTTP/1.1:New protocol is more cache-aware, 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
Technologies
• Caching: Essential!
• HTTP/1.1:New protocol is more cache-aware, 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
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XMLXML:
• Extensible Markup Language• A lightweight SGML designed for network use• Support from SGML and browsers vendors• Proposals for variety of applications:
– CML (Chemical Markup Language) – MML (Maths ..)– XML Web Collections – Privacy & Profiling– RDF (Resource Description Framework) – CDF (Channel Definition Format)– DRP (Distribution and Replication Protocol)
• See http://www.textuality.com/xml/http://www.w3.org/XML/
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Push Technologies
Use of push technologiesWhy: Push information,
teaching and learning services to end users
Barriers: Lack of standards, bandwidth concerns
How: CDF, ...
Familiarisation: PointcastIE 4, Netscape
See http://www.w3.org/Architecture/9709_Workshop/
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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
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UKOLN's WebWatch ProjectWebWatch:
• 1 year post funded by British Library (BLRIC)• Ian Peacock ([email protected])• 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
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WebWatch Aims
Aim to:• Analyse communities:
– Public libraries – eLib pages – UK HE home pages – Institutional pages
• Provide useful information and statistics:– Size and extend of website– Technologies used – …
• Provide set of tools• Useful for:
– Funding bodies, trainers, institutional web teams, support staff, advisors. etc
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WebWatch - Architecture
Makes use of Harvest
Stores SOIF records describing resources:file-type{4}: html
p-count{1}: 9
script-count{1}: 2
...
url-refs{23}: http://www.ukoln.ac.uk/
file-type{5}: image
image-type{3}: gif
nos-colours{3}: 128
Counting HTML elements
Recording attribute values
Details for other resourcese.g. image
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Log Analysis
Need to:• Monitor user agents• Platform issues (Win v Mac, 16 bit v 32 bit)• Use of HTTP headers
Useful for:• Establishing timeliness of new technologies• Caching communities
Privacy implications
Can:• Access files directly (subject to AUP)• Copy anonymised log files for processing
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WebWatch Launch Plans
1. UK HE Institutional Home PagesWhat?
• Sizes of objects (HTML, images, etc.)• Profile (nos. of images, links, graphics, CGI)• Quality (broken links, HTML conformance)• HTML element usage (metadata, tables, scripting)
Stakeholders• Institutional web teams, web policy groups, trainers• Caching communities
2. UK Public Library Web SitesWhat?
• Extent of web site (size, nos. of pages, …)• ...
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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
• WebWatch can assist by monitoring developments within the community
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Questions
Any Questions?
Feedback on WebWatch