A centre of expertise in digital information managementwww.ukoln.ac.uk HTML Is Dead! A Web Standards Update Brian Kelly UK Web Focus UKOLN University of Bath Bath URL UKOLN is supported by:

A centre of expertise in digital information managementwww.ukoln.ac.uk 2 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 Aims of Talk To give brief overview of Web architecture To describe developments to Web standards To briefly address implementation models

A centre of expertise in digital information managementwww.ukoln.ac.uk 3 Standards in an Educational / Research Context 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

A centre of expertise in digital information managementwww.ukoln.ac.uk 4 Standards 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! 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? 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? Standards

A centre of expertise in digital information managementwww.ukoln.ac.uk 5 Standards and the Web W3C Produces W3C Recommendations on Web protocols Managed approach to developments Protocols initially developed by W3C members Decisions made by W3C, informed by member & public review IETF Produces Internet Drafts on Internet protocols Bottom-up approach to developments Protocols may be developed by interested individuals "Rough consensus and working code" ISO Produces ISO Standards Can be slow moving and bureaucratic Produce robust standards Proprietary De facto standards Often initially appealing (cf PowerPoint, PDF) May emerge as standards PNG HTML Z39.50 Java PNG HTML Z39.50 Java HTML, XML, PNG, … HTTP URN whois++ HTTP URN whois++ HTML extensions PDF and Java? HTML extensions PDF and Java? Standards

A centre of expertise in digital information managementwww.ukoln.ac.uk 6 The Case For W3C 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

A centre of expertise in digital information managementwww.ukoln.ac.uk 7 Standards, Architectures, Applications, Resources This talk touches on several areas Architectures: models for implementing systems Standards: concerned with protocols and file formats Open standards vs. Proprietary HTML / XML vs. PDF CSS / XSL vs. HTML GIF vs PNG Which standards are applicable NT / Unix File system / database application HTML tools / content management 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 Resources: financial and staff costs needed to implement systems Applications: software products used to implement systems Standards

A centre of expertise in digital information managementwww.ukoln.ac.uk 8 GIF 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 WARNING: There is no guarantee that payment will not be required for proprietary file formats which are currently free Standards

A centre of expertise in digital information managementwww.ukoln.ac.uk 9 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 The Netsoft home page 1User clicks on link to the address (URL) 2Browser converts link to HTTP command (METHOD): Connect to computer at GET /hello.html 3Remote computer sends file Welcome to Netsoft 4Local computer displays HTML file Web Browser Web server Welcome.. The Netsoft home page

A centre of expertise in digital information managementwww.ukoln.ac.uk 10 Approaches To HTML 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? Issues Should we stop giving HTML training courses? Should we stop buying HTML authoring tools? Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 11 XML XML: Extensible Markup Language A lightweight SGML designed for network use Addresses HTML's lack of evolvability Arbitrary elements can be defined (,, 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 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 12 XML Concepts (1) Well-formed XML resources: Make end-tags explicit:... Make empty elements explicit: Quote attributes <img src="logo.gif" height="20" Use consistent upper/lower case and are different XML Namespaces: Mechanism for ensuring unique XML elements : Insert M-471 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 13 XML Concepts (2) 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 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 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 14 XML Concepts (3) 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 XPointer Provides access to arbitrary portions of XML resource See England France Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 15 Getting to XML With XHTML XHTML: HTML represented in XML Some small changes to HTML:  Elements in lowercase not  Attributes must be quoted  Elements must be closed:... ) Gain benefits from XML Tools available (e.g. HTML-Kit from ) See, and Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 16 CSS 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 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 17 SVG SVG: Scalable Vector Graphics A language for describing two-dimensional graphics in XML See Also see presentation on XML written in SVG at WWW 2002 talk at Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 18 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 19 SVG Example Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 20 SVG and XSLT 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 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 21 CML, SVG and XSLT A molecule described in CML can be transformed using XSLT into SVG, allowing it to be displayed and manipulated

A centre of expertise in digital information managementwww.ukoln.ac.uk 22 SMIL 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 Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 23 SMIL Example basics/animation/svg_smil/index.htm

A centre of expertise in digital information managementwww.ukoln.ac.uk 24 MathML MathML: An XML application for maths Various plugins, dedicated readers, etc. Mozilla renders natively See

A centre of expertise in digital information managementwww.ukoln.ac.uk 25 Modularisation 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 and Data Formats

A centre of expertise in digital information managementwww.ukoln.ac.uk 26 Web Standards Part 2 –Deployment Issues

A centre of expertise in digital information managementwww.ukoln.ac.uk 27 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.

A centre of expertise in digital information managementwww.ukoln.ac.uk 28 Architectures Let us consider the following areas: Content Management Access (Browser support) Deployment

A centre of expertise in digital information managementwww.ukoln.ac.uk 29 Position Today 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. Deployment

A centre of expertise in digital information managementwww.ukoln.ac.uk 30 The CMS To The Rescue 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? Issues CMS can be expensive CMS can be free but have support implications Which one to choose? Deployment

A centre of expertise in digital information managementwww.ukoln.ac.uk 31 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. 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. 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. 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?

A centre of expertise in digital information managementwww.ukoln.ac.uk 32 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!

A centre of expertise in digital information managementwww.ukoln.ac.uk 33 Questions Any questions?