1 future of the web brian kelly, uk web focus ukoln university of bath bath, ba2 7ay ukoln is...

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Future Of The Web

Brian Kelly, UK Web Focus

UKOLN

University of Bath

Bath, BA2 7AY

http://www.ukoln.ac.uk/UKOLN is funded by the British Library Research and Innovation Centre, the Joint Information Systems Committee of the Higher Education Funding Councils, as well as by project funding from the JISC’s Electronic Libraries Programme and the European Union. UKOLN also receives support from the University of Bath where it is based.

UKOLN is funded by the British Library Research and Innovation Centre, the Joint Information Systems Committee of the Higher Education Funding Councils, as well as by project funding from the JISC’s Electronic Libraries Programme and the European Union. UKOLN also receives support from the University of Bath where it is based.

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Contents

Data Formats• HML 4.0 • CSS 2.0• Dynamic HTML • XML

Transport• HTTP/1.1

Addressing• URLs • URNs • DOIs

Metadata• PICS • RDF

Implications for the Community

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Web Protocols

The web was originally based on 3 protocols:

• Data Format (user interface): HTML

• Transport: HTTP

• Addressing: URLs

Data format Transport

Addressing

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HTML

HTML:• Defines structure• SGML application• Platform and application independent• Simple and therefore easy to create

but:• Netscape / Microsoft browser wars began• HTML extensions appeared• (Proprietary) scripting languages add new

functionality and also complexity• Universal access begins to be lost

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HTML Develops

During 1997 recognition of dangers of HTML wars

Netscape and Microsoft began working with W3C on development of new protocols

HTML 4.0• W3C recommendation• Primarily defines structure• Layout tags for backwards compatibility

CSS 2.0• W3C draft• Used to define appearance

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CSS 1

CSS level 1:• W3C recommendation in December 1996• Partly supported in IE 3.0• Early designs attempts confirmed power of CSS

but highlighted backwards compatibility issues

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CSS 2

CSS level 2:• Provides richer functionality• Addressed backwards compatibility issues

http://www1.shore.net/~straub/wprmultb.htm

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Making HTML Dynamic

DOM: • Document Object Model• W3C activity• Enables client-side scripting languages to

manipulate HTML and CSS elements and their content

• Sometimes referred to as dynamic HTML

But:• Netscape's implementation is non-standard

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DHTML Example - 1

Making documents "collapsible" is very easy:on mouseclick in heading

set visibility and display of body off

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DHTML Example - 2

Dynamic HTML can be used to develop improved user interfaces.

In this example an expanded menu is provided.

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DHTML Example - 3

DHTML can be used to provide interactive systems - e.g. for CBL, simulation

In this example the pieces can be moved.

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Compatibility IssuesCompatibility with old browsers / other browsers can be provided by:• Using safe, backwards

compatible features• Checking for browser

type by client-side scripting language

• Checking for browsertype by server

Alternatively ignore backwards compatibility

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Using DHTML Locally

Can create a variety of dynamic sitemaps

Your website

Your pointers

Remote websites

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Information Landscapes

Developments such as Web Collections will enable metadata for groups of related resources to be defined for:

• Providing enhanced user navigation• Facilitating printing, off-line browsing, ...• Facilitating indexing• etc.

The term Information Landscapes has been coined to refer to changing, configurable views of networked resources

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Information Landscapes

Landscapes can be developed by / for:• Institutions • Groups (e.g. undergrads)• Service providers • ...

Information Landscapes can be used for delivering information based on:

• Institutional needs and interests• End user's technologies / interface preferences

Implications:• Ownership, legal and copyright issues• Change control • Visibility• Maintenance

What demand is there?

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The End for HTML?

HTML 4.0 and CSS 2.0 provide a rich environment for describing document structure and appearance

But:• Standardisation of new elements is slow

• Supporting communities with specific needs (e.g. Maths) will result in large, complex HTML

• Applications have specific needs (e.g. <STUDENT-NUMBER>

• HTML 5, 6, … does not appear to resolve these issues

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XML

XML:• Extensible Markup Language• Can be regarded as a lightweight SGML• Supported by SGML community• Some support in Internet Explorer 4.0• Netscape promising support in future• XML 1.0 became a W3C recommendation

in Feb 1998• See <URL:http://www.w3.org/XML/>

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XML Applications

MML / CMLScientific communities have defined Math and Chemical Markup Languages

CDFChannel Definition Format provides a proposed standard for push technologies

RDFResource Description Framework provides a proposed standard for a metadata architecture

...

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CDF Example

NewsAgent:• an eLib project• evaluating potential

for CDF for pushing information

Software such as FrontPage 98 have CDF wizards

http://newsagent.ukoln.ac.uk/channel/

<CHANNEL HREF="http://newsagent.ukoln.ac.uk/channel/top.cdf"><LASTMOD="1998-03-05T00:39" /><SCHEDULE> <INTERVALTIME DAY="1"/></SCHEDULE ><ITEM HREF="http://newsagent.ukoln.ac.uk/channel/Events.html"><TITLE>Events</TITLE> </ITEM> Typical CDF File

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Transport

HTTP 1.0 Widely used Inefficient Cache unfriendly

HTTP/1.1 Addresses deficiencies in HTTP/1.0 Cache-aware Available now (e.g. latest version of Apache) Supported in ~ 40% of UK HEIs Browser support?

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Addressing

URLs:• Provide addressing for the web• Consider http://www.dec.com/internet/applications/

• Problems:– Company reorganises website– Individual leaves– Company is taken over!

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Solutions (1)

URNs:Uniform Resource Names: make identification of Internet documents possible.

URN identifiers are persistent and unique.

See <URL: http://www.ietf.org/html.charters/urn-charter.html>

PURLs:Persistent URLs: Point to a resolution services rather than the resource itself.

See <URL: http://purl.oclc.org/>

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Solutions (2)DOIs:

• Document Object Identifiers• Costs $1,000 to register

http://hdl.handle.net/10.1016/S1384107697000225

http://hdl.handle.net/10.1016/S1384107697000225

hdl://cnri.dlib/august95-contentshdl://cnri.dlib/august95-contents

DOIs use CNRI's Handles

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Addressing: Conclusions

Conclusions:• No clear technological winner• Performance issues• Is it just for "publishers"• Business model uncertain• Backwards compatibility and "real world

citation" issues• Still need for information providers to give

careful thought to URL naming schemes

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Metadata

Metadata:• The missing architectural component of the Web• Many developments in progress:

– PICS: "this resource contains bad language rated as X" – Dublin Core: the author's name is xxx and his email

address is yyy

– Web Collections: these set of resources are related and should be download together / printed as a single document / …

– Distributed Authoring: the following can update this document

– ...

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RDF

Resource Description Framework (RDF):• Generic infrastructure for metadata• Based on XML• See <URL:http://www.w3.org/RDF/>

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Using The Technologies

How / when are new technologies to be deployed?• Use "safe" features to ensure backwards compatibility• Check for browser functionality at server• Check for browser functionality at client• Deploy on Intranet for access to internal resources /

external resources• Use tools which can regenerate systems when

standards change / develop• Which tools?• Need to avoid the "tyranny of the template"

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Web ArchitectureWeb architecture is:

• Growing in complexity• Maturing,

becoming more robust

Must understand architecture to avoid:

• Escalating costs

• Degradation of service quality / functionality

Data format

Transport

Address-ing

Metadata

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Community Issues

Issues which the community need to address:• Can we agree on a minimum recommended

browser spec?• Can we use more sophisticated technologies to

cater for variety of browser technologies?• How can we share experiences / knowledge of

what we're doing?

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WebWatch

Project based at UKOLN to monitor web developments in UK

Analysed various communities:

• University entry points• eLib projects• Public libraries

Server software

Nos. of hyperlinks

File size (HTML)

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Web Focus ROADS GatewayA ROADS gateway (software used by SOSIG, OMNI, etc. gateways) being developed to support UK HE web teams:

• AUPs• Guidelines• …

Your feedback needed

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Questions?