HTML Is Dead! A Web Standards Update

UKOLN is supported by: HTML Is Dead!A Web Standards Update Brian Kelly UK Web Focus UKOLN University of Bath Bath Email B.Kelly@ukoln.ac.uk URL http://www.ukoln.ac.uk/

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

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)

Standards Standards Before the Web Access to resources typically required use of software vendor’s 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!

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, …

The Case For W3C Standards Standards • Why use open standards developed by the W3C? Why not leave it to the marketplace? • W3C’s 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 • W3C’s open standards have been developed to interoperate with each other according to W3C’s design vision • Commercial companies typically develop proprietary formats in isolation, or along the lines of a company vision

Standards, Architectures, Applications, Resources Standards • This talk touches on several areas Standards: concerned with protocols and file formats Architectures: models for implementing systems 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 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

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 <http://burnallgifs.org/> • WARNING: • There is no guarantee that payment will not be required for proprietary file formats which are currently free

Welcome to Netsoft 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 Netsofthome page 3 Remote computer sends file <HTML> <TITLE>Welcome</TITLE>.. The <A HREF=“…”>Netsoft</A> home page Web server 4 Local computer displays HTML file

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?

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 (<STUDENT-NUMBER>, <PART-NO>, 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

XML Concepts (1) Data Formats • Well-formed XML resources: Make end-tags explicit: <li>...</li> Make empty elements explicit: <img .../> Quote attributes <imgsrc="logo.gif" height="20" Use consistent upper/lower case and are different • XMLNamespaces: Mechanism for ensuring unique XML elements: <?xml:namespace ns="http://foo.org/1998-001" prefix="i"> Insert <i:PART>M-471</i:PART>

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 <http://www.w3.org/XML/Schema> • 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 <http://www.xslt.com/>

England France 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 <http://www.xml.com/pub/a/2000/09/xlink/> • XPointer • Provides access to arbitrary portions of XML resource • See <http://www.w3.org/TR/xptr/>

Getting to XML With XHTML Data Formats • XHTML: • HTML represented in XML • Some small changes to HTML: • Elements in lowercase not • Attributes must be quoted <img src="logo" height="50"> • Elements must be closed: ... ) <img src="logo" ... /> • Gain benefits from XML • Tools available (e.g. HTML-Kit from http://www.chami.com/html-kit/) • See <http://www.webreference.com/xml/column6/>, <http://groups.yahoo.com/group/XHTML-L/> and <http://www.ariadne.ac.uk/issue27/web-focus/>

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 <http://www.w3c.org/Style/CSS/>

SVG Data Formats • SVG: • Scalable Vector Graphics • A language for describing two-dimensional graphics in XML • See <http://www.w3.org/Graphics/SVG/Overview.htm8> • Also see presentation on XML written in SVG at <http://www.w3c.org/Talks/2001/12/IH-Euroweb/W3CInTheWorldslide.svgz> • WWW 2002 talk at <http://www.w3c.org/2002/Talks/www2002-SVG/>

Data Formats

SVG Example Data Formats http://www.karto.ethz.ch/neumann/cartography/vienna/

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/

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

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 <http://www.w3c.org/AudioVideo/>

http://www.reseau.it/smil/smilapp_en.html http://www.kevlindev.com/tutorials/basics/animation/svg_smil/index.htm SMIL Example

MathML • MathML: • An XML application for maths • Various plugins, dedicated readers, etc. • Mozilla renders natively See <http://www.mozilla.org/projects/mathml/>

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 <http://www.w3.org/TR/xhtml-modularization/> and<http://www.xml.com/pub/a/2002/01/16/xhtml-m12n.html>

Web StandardsPart 2 –Deployment Issues

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.

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

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.

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?

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 youshould 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.

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!

Questions • Any questions?

HTML Is Dead! A Web Standards Update