HTML%20Is%20Dead!%20A%20Web%20Standards%20Update

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HTML Is Dead!A Web Standards Update

• Brian Kelly
• UK Web Focus
• UKOLN
• University of Bath
• Bath

Email B.Kelly_at_ukoln.ac.uk URL http//www.ukoln.ac.
uk/
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Contents

• Introduction
• Standards
• The Original Web Architecture
• Architectural Developments
• Deployment Issues
• Discussion

• Aims of Talk
• To give brief overview of Web architecture
• To describe developments to Web standards
• To briefly address implementation models

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Standards in an Educational / Research Context
Standards

• Standards are important in a public sector
  context (e.g. education, research, central
  local government, ...) context to
• Ensure widespread access to resources
• Enables resources to be reused and repurposed
• Ensure scholarly resources can be preserved
• Address accountability of public funding
• Minimise resource costs for upgrading systems
• Provide universal access to resources (cf
  disability legislation)

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Standards
Standards
Before the Web Access to resources typically
required use of software vendors software
which was only available on limited no. of
platforms. Often the software would be
licensed. The goal of the Web was to provide
universal access to resources. Who could argue
with this goal?

• Need for standards to provide
• Platform and application independence
• Avoidance of patented technologies
• Flexibility and architectural integrity
• Long-term access to data
• Ideally look at standards first, then find
  applications which support the standards.
  However it can be difficult to achieve this ideal!

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Standards and the Web
Standards

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

HTML extensions PDF and Java?
PNG HTML Z39.50 Java

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

• 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 may be developed by interested
  individuals
• "Rough consensus and working code"

HTTP URNwhois
HTML, XML, PNG,
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The Case For W3C Standards
Standards

• Why use open standards developed by the W3C? Why
  not leave it to the marketplace?
• W3Cs open standards have been developed in an
  open environment, with the aim of achieving
  platform and application independency
• Commercial companies develop proprietary formats
  in order to maximise their profits and dividends
  to shareholders
• W3Cs open standards have been developed to
  interoperate with each other according to W3Cs
  design vision
• Commercial companies typically develop
  proprietary formats in isolation, or along the
  lines of a company vision

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Standards, Architectures, Applications, Resources
Standards

• 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 GIF vs PNG
Resources financial and staff costs needed to
implement systems
Applications software products used 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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GIF
Standards

• As an example of the dangers of use of
  proprietary solutions, consider the GIF file
  format
• Unisys announce that they hold patent to
  compression algorithm used in GIF images and
  users of GIF will have to pay
• Following much debate, Unisys require payment for
  licence from software developers - and also for
  end users of unlicensed software (5,000!)
• Web community responds with PNG format
• See lthttp//burnallgifs.org/gt
• WARNING
• There is no guarantee that payment will not be
  required for proprietary file formats which are
  currently free

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How Does The Web Work?

• The Web has three 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
Web Browser
2 Browser converts link to HTTP command
(METHOD) Connect to computer at
www.netsoft.com GET /hello.html
The Netsoft home page
3 Remote computer sends file
ltHTMLgt ltTITLEgtWelcomelt/TITLEgt.. ltPgtThe ltA
HREFgtNetsoftlt/Agt home pagelt/Pgt
Web server
4 Local computer displays HTML file
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Approaches To HTML
Data Formats

• Emphasis on managing HTML resources
  inappropriate
• HTML is an output format, which cannot easily be
  reused (e.g. WAP, e-Books, etc.)
• Need to manage HTML fragments (only partly
  achievable with SSIs)
• Need to manage collections of resources
• Need to have single master source of data
• Need to support new developments such as
  personalisation
• Difficult to integrate with new formats

• Issues
• Should we stop giving HTML training courses?
• Should we stop buying HTML authoring tools?

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XML
Data Formats

• 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 latest versions of Web browsers

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XML Concepts (1)
Data Formats

• 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 ltpgt and ltPgt are
  different
• 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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XML Concepts (2)
Data Formats

• XML Schemas
• Allow constraints to be applied on XML attributes
• Express shared vocabularies and allow machines to
  carry out rules made by people
• Richer than DTDs
• See lthttp//www.w3.org/XML/Schemagt
• XSLT
• A language for transforming XML from one DTD to
  another, or to another format (e.g. PDF)
• Written in XML
• Knows about XML (e.g. tree structures, etc.)
• See lthttp//www.xslt.com/gt

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XML Concepts (3)
Data Formats

• XLink sophisticated hyperlinking
• Links that allow you to choose multiple
  destinations
• Bidirectional links
• Links with special behaviours
• Expand-in-place / Replace / Create new window
• Link on load / Link on user action
• Link databases
• See lthttp//www.xml.com/pub/a/2000/09/xlink/gt
• XPointer
• Provides access to arbitrary portions of XML
  resource
• See lthttp//www.w3.org/TR/xptr/gt

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Getting to XML With XHTML
Data Formats

• XHTML
• 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)
• 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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CSS
Data Formats

• CSS
• Cascading Style Sheets
• XHTML/XML defines structure, CSS describes the
  appearance
• CSS 1.0 and 2.0 now W3C recommendations
• CSS 3.0 in preparation (modularised)
• We should be using CSS
• Part of architecture
• Ease of maintenance
• Becoming much richer
• Accessibility
• See lthttp//www.w3c.org/Style/CSS/gt

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SVG
Data Formats

• SVG
• Scalable Vector Graphics
• A language for describing two-dimensional
  graphics in XML
• See lthttp//www.w3.org/Graphics/SVG/Overview.htm8
  gt
• Also see presentation on XML written in SVG at
  lthttp//www.w3c.org/Talks/2001/12/IH-Euroweb/W3CI
  nTheWorldslide.svgzgt
• WWW 2002 talk at lthttp//www.w3c.org/2002/Talks/w
  ww2002-SVG/gt

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Data Formats
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SVG Example
Data Formats
http//www.karto.ethz.ch/neumann/cartography/vienn
a/
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SVG and XSLT
Data Formats

• This example
• Originally written in Java
• Author realised that XSLT would be easier
• Uses SVG for chess board and pieces
• Uses XSLT to move pieces

http//people.w3.org/maxf/ChessGML/
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CML, SVG and XSLT
http//www.adobe.com/svg/demos/cml2svg/html/index.
html

• A molecule described in CML can be transformed
  using XSLT into SVG, allowing it to be displayed
  and manipulated

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SMIL
Data Formats

• SMIL
• Synchronized Multimedia Integration Language
• A language for authoring of interactive
  audiovisual presentations
• Allows you to synchronize text, images, audio and
  video in a document
• An XML Application
• See lthttp//www.w3c.org/AudioVideo/gt

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SMIL Example
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MathML

• MathML
• An XML application for maths
• Various plugins, dedicated readers, etc.
• Mozilla renders natively

See lthttp//www.mozilla.org/projects/mathml/gt
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Modularisation
Data Formats

• How can you
• Include XML resources such as MathML, ChemML, etc
  in XHTML documents?
• Provide a subset of XHTML features in browsers on
  devices such as mobile phones, PDAs, etc.?
• The answer is
• XHTML modularisation (modularization )
• See lthttp//www.w3.org/TR/xhtml-modularization/gt
  andlthttp//www.xml.com/pub/a/2002/01/16/xhtml-m1
  2n.htmlgt

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Web StandardsPart 2 Deployment Issues
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W3C Challenges

• W3C faces a number of challenges
• Commercial acceptance (cf. browser wars)
• Software vendors may refuse to deploy new
  standards
• User acceptance
• User may not use of new standards (it's too
  complex / expensive, )
• Patent issues
• Software vendors may claim patents on new
  standards
• Complexity
• The wide range of new standards makes deployment
  too difficult
• Organisational issues
• W3C is facing too many difficulties in growth,
  politics, etc.

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Architectures
Deployment

• Let us consider the following areas
• Content Management
• Access (Browser support)

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Position Today
Deployment

• What should we be doing today?
• Move away from creating new content in HTML
• Move to XHTML as part of the migration
• Deploying XML applications
• Storing structured information in a neutral
  database
• Using a CMS to manage our content
• Deploying B2B applications to avoid human
  bottleneck (such as RSS)

Note that these are aspirations. We will, of
course, be constrained by existing systems,
resource implications, vested interests, inertia,
etc.
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The CMS To The Rescue
Deployment

• HTML authoring tools have limitations (as has
  HTML).
• A CMS (Content Management System)
• Allows fragments to be managed
• Allows collections to be managed
• Allows resources to be stored in a neutral format
  (backend database)
• Allows resources to be reused
• Often provides access control
• Often provides workflow processes and project
  management

• Issues
• CMS can be expensive
• CMS can be free but have support implications
• Which one to choose?

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Browser Issues

• Which approach to browser issues should you take?

Web sites should be usable to old browsers as
these are still in use and we aim to maximise
access. Therefore you should deliver HTML 3.2 /
4.0 and avoid technologies such as JavaScript and
CSS.

• NOTE
• Use of clean HTML should degrade gracefully
• XHTML is a useful transition
• User-agent negotiation may be relevant
• QUESTION
• Should organisations / community implement a
  browser policy?

Old browsers are broken and fail to implement new
technologies which provide (a) richer
functionality (b) support for new devices and (c)
better support for people with disabilities.
Therefore you should use the latest stable
versions of HTML (XHTML), CSS, etc.
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Conclusions

• To conclude
• The Web has not yet stabilised
• New developments provide needed functionality or
  address current limitations
• However W3C cannot guarantee that its vision will
  necessarily be implemented
• There is therefore a risk and a cost in adopting
  new standards
• There is also a risk in failing to adopt new
  standards!
• Keeping up-to-date is therefore essential!

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Questions

• Any questions?