The%20Latest%20Web%20Developments

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The Latest Web Developments

• Brian Kelly
• UK Web FocusUKOLN
• University of Bath
• Bath, BA2 7AY

Email B.Kelly_at_ukoln.ac.uk URL http//www.ukoln.ac.
uk/
UKOLN is supported by
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About Me

• Brian Kelly
• UK Web Focus a JISC-funded post to advise HE
  and FE communities on Web developments
• Based in UKOLN (UK Office for Library and
  Information networking) a small applied
  research organisation in University of Bath
• Involved in Web since 1993, while working in
  Computing Service at University of Leeds
• Close links with Computing Service and Library
  communities

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About You

• What is your involvement with the Web?
• What topics would you like covered today?

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Possible Interests
Web applications
XML
File formats
Content Management Systems
Hyperlinking
Interests
Legal issues
Technologies
RDF
When is it going to stabilise?
Whats happening to HTML?
Web browsers
Web Standards
Netscape or Microsoft?
Web Architectures
Open source vs licensed apps
Web Applications
Web Services
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Contents

• Standards and the Web
• The Original Web Architecture
• The Problems
• Architectural Developments
• Metadata
• New Developments
• Deployment Issues
• Discussion

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Standards, Architectures, Applications, Resources

• This talk touches on several areas

Architectures models for implementing systems
Standards concerned with protocols and file
formats
Which standards are applicable NT / UnixFile
system / database application HTML tools /
content management
Open standards vs. Proprietary HTML / XML vs.
PDF CSS / XSL vs. HTML
Applications software products used to implement
systems
Resources financial and staff costs needed to
implement systems
Apache / IIS FrontPage / Dreamweaver Oracle /
SQLServer ColdFusion vs ASP
Development vs. Migration costs Use of in-house
expertise In-house vs. out-sourced Licensed vs.
open source
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Standards

• Need for standards to provide
• Platform independence
• Application independence
• Avoidance of patented technologies
• Flexibility ("evolvability" - Tim Berners-Lee)
• Architectural integrity
• Long-term access to data
• Ideally look at standards first, then find
  applications which support the standards
• Difficult to achieve this ideal!

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Deployment Issues

• What part of the spectrum are you closest to?

Must support standards
Go with the marketplace
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I Support Standards

• But
• You probably use PowerPoint, don't you?
• Software vendors will subtly suck you into use of
  proprietary features
• Home-grown solutions can be expensive (where are
  all the good Perl / C programmers willing to work
  on short-term contracts for a pittance in
  Universities?)
• Standards may not take off remember Coloured
  Book network protocols?
• Proprietary solutions may become standardised
• Standards may not yet be available (or finalised)
• Do users want standards? Will "We support
  standards" conflict with "Our services are based
  on user requirements"?

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I Follow The Marketplace

• Good New Labour philosophy, but
• Can you trust your software vendor?
• Will your software vendor be around in a few
  years time ("I only buy Rover")
• Will your system be interoperable?
• What happens when you want to interwork with
  partners or your organisation merges / is taken
  over?
• What happens when you want to extend your system
  beyond the limits set by your software vendor?

IBM was the market leader in the 1970s, but lost
out in the PC revolution What will happen if
Microsoft is split in two?
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Some Difficulties

• We should acknowledge some difficulties in a
  standards-based approach
• Keeping up-to-date (look at nos. of documents at
  http//www.w3c.org/TR/ and size of
  http//www.diffuse.org/standards.html)
• Spotting the winning standards
• Implementing the standard in a timely way
• Dealing with the problems of the software vendor
• Resources!

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Standardisation

• Other
• Standards bodies such as ECMA
• Community groups which can agree on, say, profiles

HTML extensions PDF and Java?

• Proprietary
• De facto standards
• Often initially appealing (cf PowerPoint)
• May emerge as standards

• W3C
• Produces W3C Recommendations on Web protocols
• Managed approach to developments
• Protocols initially developed by W3C members
• Decisions made by W3C, influenced by member and
  public review

PNG HTML Z39.50 Java?

• ISO
• Produces ISO Standards
• Can be slow moving and bureaucratic
• Produce robust standards

• IETF
• Produces Internet Drafts on Internet protocols
• Bottom-up approach to developments
• Protocols developed by interested individuals
• "Rough consensus and working code"

HTTP URNwhois
PNG HTML HTTP
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World Wide Web Consortium

• Much of the development of Web standards is being
  coordinated by the W3C
• W3C (World Wide Web Consortium)
• International consortium, with headquarters at
  MIT, INRIA and Keio University (Japan)
• Coordinates development of web protocols
• Four domains
• Architecture Technology Society
• User Interface Web Accessibility

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The Web Vision

• Tim Berners-Lee's vision for the Web
• Automation of information management If a
  decision can be made by machine, it should
• All structured data formats should be based on
  XML
• Migrate HTML to XML
• All logical assertions to map onto RDF model
• All metadata to use RDF

A useful overview of Tim Berners-Lee's vision for
the Web is given in his book Weaving The Web.
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How Does The Web Work?

• The Web has 3 fundamental concepts
• URLs addresses of resources
• HTTP dialogue between client and server
• HTML format of resources

1 User clicks on link to the address
(URL)http//www.netsoft.com/hello.html
The Netsoft home page
2 Browser converts link to HTTP command
(METHOD) Connect to computer at
www.netsoft.com GET /hello.html
Welcome to Netsoft
3 Remote computer sends file
ltHTMLgt ltTITLEgtWelcomelt/TITLEgt.. ltPgtWelcome to
ltBgtNetsoftlt/Bgt
Web server
Web Browser (client)
4 Local computer displays HTML file
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Web Protocols

• Web initially based on three simple protocols
• Data FormatsHTML (HyperText Markup Language)
  provides the data format for native documents
• AddressingURLs (Uniform Resource Locator)
  provides an addressing mechanism for web
  resources
• TransportHTTP (HyperText Transfer Protocol)
  defines transfer of resources between client and
  server

Transport HTTP
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HTML 4.0, CSS 2.0 DOM 1.0

• HTML 4.0 used in conjunction with CSS 2.0
  (Cascading Style Sheets) and DOM 1.0 provides an
  architecturally pure, yet functionally rich
  environment

• HTML 4.0
• Improved forms
• Hooks for stylesheets
• Hooks for scripting languages
• Table enhancements
• Better printing

• CSS 2.0
• Support for all HTML formatting
• Positioning of HTML elements
• Multiple media support

• DOM 1.0
• Document Object Model
• Hooks for scripting languages
• Permits changes to HTML CSS properties and
  content

• CSS Problems
• Changes during CSS development
• Netscape IE incompatibilities
• Continued use of browsers with known bugs

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CSS
http//www.w3c.org/Style/CSS/

• CSS
• Cascading Style Sheets
• An open standard developed by W3C
• Separates document structure (defined in
  HTML/XML) from the appearance
• Makes maintenance of resources much easier

body background blue h1 font-family arial
p font-family timestext-align justify
ltlink rel"style" src"sty.css" lth1gtHeadinglt/h1gt lt
pgtlt/pgt
Imagine 10,000 HTML files ..
With 1 CSS file
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Limitations

• HTML 4.0 / CSS 2.0 have limitations
• Difficulties in introducing new elements
• Time-consuming standardisation process (ltABBREVgt)
• Dictated by browser vendor (ltBLINKgt, ltMARQUEEgt)
• Area may be inappropriate for standarisation
• Covers specialist area (maths, music, ...)
• Application-specific (ltSTUD-NUMgt)
• HTML is a display (output) format
• HTML's lack of arbitrary structure limits
  functionality
• Find all memos copied to John Smith
• How many unique tracks on Spice Girls CDs

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XML

• XML
• Extensible Markup Language
• A lightweight SGML designed for network use
• Addresses HTML's lack of evolvability
• Arbitrary elements can be defined
  (ltSTUDENT-NUMBERgt, ltPART-NOgt, etc)
• Agreement achieved quickly - XML 1.0 became W3C
  Recommendation in Feb 1998
• Support from industry (SGML vendors, Microsoft,
  etc.)
• Support in Netscape 6 (?) and IE 5

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XML Concepts

• Well-formed XML resources
• Make end-tags explicit ltligt...lt/ligt
• Make empty elements explicit ltimg ... /gt
• Quote attributes ltimg src"logo.gif" height"20"
• Use consistent upper/lower case
• Valid XML resources
• Need DTD
• XML Namespaces
• Mechanism for ensuring unique XML elements
• lt?xmlnamespace ns"http//foo.org/1998-001"
  prefix"i"gt
• ltpgtInsert ltiPARTgtM-471lt/iPARTgtlt/pgt

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More XML Developments

• Momentum behind XML is driving additional
  standardisation developments
• XML PathA language for addressing parts of an
  XML document, designed to be used by XSLT and
  XPointer
• XML Schemas (Ii)Defining the nature of XML
  schemas and their component parts
• XSLTA language for transforming XML documents
  into other XML documents

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XHTML

• XHTML
• Extensible Hypertext Markup Language
• HTML represented in XML
• Some small changes to HTML
• Elements in lowercase (ltpgt not ltPgt)
• Attributes must be quoted (ltimg src"logo"
  height"50"gt
• Elements must be closed (lt p gt..lt/ p gt)
• Empty elements must be closed (ltimg src"logo" .
  /gt)
• Gain benefits from XML
• Tools available (e.g. HTML-Kit from
  http//www.chami.com/html-kit/)
• See lthttp//www.webreference.com/xml/column6/gt,
  lthttp//groups.yahoo.com/group/XHTML-L/gt and
  lthttp//www.ariadne.ac.uk/issue27/web-focus/gt

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Transport

• HTTP/0.9 and HTTP/1.0
• Design flaws and implementation problems
• HTTP/1.1
• Addresses some of these problems
• 60 server support
• Performance benefits! (60 packet traffic
  reduction)
• Is acting as fire-fighter
• Not sufficiently flexible or extensible
• HTTP/NG
• Radical redesign using object-oriented
  technologies
• Undergoing trials
• Gradual transition (using proxies)
• Moving slowly

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Addressing

• URLs (e.g. http//www.bristol-poly.ac.uk/depts/mu
  sic/) have limitations
• Lack of long-term persistency
• Organisation changes name
• Department shut down or merged
• Directory structure reorganised
• Inability to support multiple versions of
  resources (mirroring)
• URNs (Uniform Resource Names)
• Proposed as solution
• Difficult to implement (no W3C activity in this
  area)

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Addressing - Solutions

• PURLs (Persistent URLs)
• Provide single level of redirection
• DOIs (Digital Object Identifiers)
• Proposed by publishing industry as a solution
• Aimed at supporting rights ownership
• Business model needed
• OpenURLs
• Address mirroring issues
• Pragmatic Solution
• URLs don't break - people break them
• Design URLs to have long life-span
• Further information
• ltURL http//www.ukoln.ac.uk/metadata/resources/ur
  n/gt
• ltURL http//www.w3.org/Provider/Style/URIgt

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Metadata

• Metadata - the missing architectural component
  from the initial implementation of the Web

• Metadata Needs
• Resource discovery
• Content filtering
• Authentication
• Improved navigation
• Multiple format support
• New devices
• Rights management

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Metadata Examples

• DSig (Digital Signatures initiative)
• Key component for providing trust on the web
• DSig 2.0 will be based on RDF and will support
  signed assertion
• This page is from the University of Bath
• This page is a legally-binding list of courses
  provided by the University
• P3P (Platform for Privacy Preferences)
• Developing methods for exchanging Privacy
  Practices of Web sites and user
• Note that discussions about additional rights
  management metadata are currently taking place

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RDF

• RDF (Resource Description Framework)
• Highlight of WWW 7 conference
• Provides a metadata framework ("machine
  understandable metadata for the web")
• Based on ideas from content rating (PICS),
  resource discovery (Dublin Core) and site mapping
  (MCF)
• Based on a formal data model (direct label
  graphs)
• Applications include
• cataloging resources resource discovery
• electronic commerce intelligent agents
• intellectual property rights privacy
• See ltURL http//www.w3.org/Talks/1998/0417-WWW7-
  RDFgt

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RSS An RDF Application

• RSS (Rich Site Summary)
• Now an RDF application
• Used for news feeds
• Of interest to JISC (DNER architecture)
• Lightweight approach that we should be
  investigating

See example of an RSS authoring tool and parser
at lthttp//rssxpress.ukoln.ac.uk/gt. Note this
service uses CGI a JavaScript solution is also
being developed.
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RDF Conclusion

• RDF is a general-purpose framework
• RDF provides structured, machine-understandable
  metadata for the Web
• Metadata vocabularies can be developed without
  central coordination
• RDF Schemas describe the meaning of each property
  name
• Signed RDF is the basis for trust

• But
• Is RDF too complex?
• Will it gain acceptance in the market place?
• The jury is till out

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Other Web Developments

• Many Web standards developments are taking place
  outside W3C
• UDDI (Universal Description, Discovery, and
  Integration) a way of describing Web services
  in a machine readable way to facilitate location
  of services by agents. See lthttp//www.uddi.org/
  gt
• Biztalk a framework for developing XML schemas
  for B2B applications. See lthttp//www.biztalk.or
  g/gt
• SOAP (Simple Object Access Protocol) - an XML
  protocol for exchange of informationSee
  lthttp//www.w3.org/TR/SOAPgt

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New Web Areas

• Initially the Web provided
• An open environment for
• sharing information
• And aimed to
• provide a rich publishing and collaborative
  environment
• The Web is now
• Widely used in closed environments (Intranets and
  Extranets, for ecommerce, etc.)
• Addressing the missing components from the
  original architecture
• Addressing universally by providing the
  infrastructure for support of new devices

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E-commerce
Example 1
http//www.w3.org/Signature/

• E-commerce
• Requires trust
• Requires security
• Is there a viable business model?
• Developments
• Digital signatures
• Public Key Infrastructure
• Athens and Sparta in UK HE

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The Mobile Web
Example 2

• The Mobile Web
• Much hype at present
• Have you used it?
• Is it usable on such a small screen with slow
  network times?
• What about the resources need to build a WAP site
  and a Web site

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The Mobile Web Comments

• Store resources in neutral format (XML) and
  generate WAP and Web
• XML open storage format
• XSLT Transform XML

XSLTrules
XML
XSLTengine
Ebook format
WML filefor WAP
XHTML for Web
3G promises multimedia and faster networks
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Is It Worth It?

• Has the Web stabilised?
• Are you thinking about WAP services?
• Will you want to (be forced to) make your Web
  service accessible?
• Will you want to deploy personalised interfaces
  (e.g. My.Oxford.ac.uk)
• Will your web service move from information
  provision to e-business?
• Do you want your University web site to use
  business-to-business (B2B) protocols to automate
  transfer of link and news items to HERO?

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What Should I Do?

• How can I best exploit new developments?
• Storing information in a structured format makes
  subsequent redevelopment easier
• Be driven initially by standards and
  architectural considerations, not by applications
• Consider use of more sophisticated web management
  tools, rather than HTML authoring tools
• An organisational standards guidelines document
  (part of a Web Strategy document) may be useful
• Don't work in isolation
• Monitor standards development (e.g. W3C)
• Listen to others in your community
• Talk and discuss issues within your community

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Authoring

• Authoring Web pages
• Was easy
• Becoming more difficult as Web becomes more
  complex
• More difficult to maintain
• For large Web sites there is a need for
• More sophisticated tools e.g. content management
  systems
• Tailoring content for devices?

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Architectural Models

• There is a need for more intelligent software
  which can process structured resources or
  reformat unstructured ones

Web server simply sends file to client File
contains redundant information (for old browsers)
plus client interrogation support
HTML resource
Web server
HTML / XML / databaseresource
IntelligentWeb server
Client proxy
Server proxy

• Intermediaries can provide functionality not
  available at client
• DOI support
• XML support
• Format conversion

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Architectural Models e.g. XML Deployment

• Ariadne issue 14 has article on "What Is XML?"
• Describes how XML support can be provided
• Natively by new browsers
• Back end conversion of XML - HTML
• Client-side conversion of XML - HTML / CSS
• Java rendering of XML
• Examples of intermediaries

See http//www.ariadne.ac.uk/issue15/what-is/
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Conclusions

• To conclude
• The Web will continue to develop
• Standards are important
• Proprietary solutions are often tempting because
• They are available
• They are often well-marketed and well-supported
• They may become standardised
• Solutions based on standards may not be properly
  supported by applications
• Metadata is big growth area
• Intermediaries may have a role to play in
  deploying standards-based solutions
• There is a continual need to keep informed

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Questions

• Any questions?