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Universal Web Accessibility: Is It Possible? Brian Kelly UK Web Focus UKOLN [email protected] Jenny Craven, Research Associate CERLIM [email protected] A joint CERLIM/UKOLN presentation 1 BK Contents • Introduction • Universal Access For All: • The Web Architecture • The People Factor • Implementation Challenges: • Current State Of UK HEI Web Sites • Accessibility and Usability • Conclusions A joint CERLIM/UKOLN presentation 2 BK The Speakers Brian Kelly: • UK Web Focus • JISC-funded advisory post • Based at UKOLN, University Of Bath Jenny Craven: • Research Associate • Based at CERLIM, Manchester Metropolitan University A joint CERLIM/UKOLN presentation 3 BK Universal Access The Web Vision The Web was developed in order to provide universal access to digital resources, and independency from: • Platforms • Applications • File formats through use of open standards A joint CERLIM/UKOLN presentation 4 BK Universal Access 5 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 A joint CERLIM/UKOLN to achieve this presentation ideal! BK Universal Access 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 A joint CERLIM/UKOLN presentation of a company vision BK Universal Access How Does The Web Work? The Web has three fundamental concepts: • URLs: addresses of resources • HTTP: dialogue between client & server • HTML: format of resources URLs HTML HTTP 1 User clicks on link to the address (URL) http://www.netsoft.com/hello.html Web Browser The Netsoft home page 2 Browser converts link to HTTP command (METHOD): Connect to computer at www.netsoft.com GET /hello.html 3 Remote computer sends file Welcome to Netsoft 4 Local presentation computer A joint CERLIM/UKOLN 7 Web server <HTML> <TITLE>Welcome</TITLE>.. <P>The <A HREF=“…”> Netsoft</A> home page</P> displays HTML file BK Universal Access HTML Is Dead! 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? • CERLIM/UKOLN Should we stop buying HTML authoring tools? A joint presentation 8 BK Universal Access XML – The Key Meta Format XML: • • • • • Extensible Markup Language A lightweight SGML designed for network use A language for describing other languages Addresses HTML's lack of evolvability Arbitrary elements can be defined (<STUDENTNUMBER>, <PART-NO>, etc) • Agreement achieved quickly - XML 1.0 became W3C Recommendation in Feb 1998 • Support from industry (SGML vendors, Microsoft, etc.) • Need for accessibility support in from start A joint CERLIM/UKOLN presentation 9 BK Universal Access XML Concepts (1) Well-formed XML resources: Make end-tags explicit: <li>...</li> Make empty elements explicit: <img ... /> Quote attributes <img src="logo.gif" height="20" Use consistent upper/lower case <p> and <P> are different XML Namespaces: Mechanism for ensuring unique XML elements e.g. a library application containing the TITLE of the XML page, the TITLE of a book and the TITLE of : <?xml:namespace ns="http://loc.org/ 1998-001" prefix="i"> <p>Book: <i:TITLE>The Bible</i:TITLE></p> <p>Borrower: <j:TITLE>Mr</j:TITLE> … A joint CERLIM/UKOLN presentation 10 BK Universal Access 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 <http://www.w3.org/XML/Schema> XSLT: • A language for transforming XML from one XML application to anothe, or to another format (e.g. PDF) • Written in XML • Knows about XML (e.g. tree structures, etc.) • See <http://www.xslt.com/> A joint CERLIM/UKOLN presentation 11 BK Universal Access XML Concepts (3) England XLink sophisticated hyperlinking: France • 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/XPath: • Provides access to arbitrary portions of XML resource • See <http://www.w3.org/TR/xptr/> A joint CERLIM/UKOLN presentation 12 BK Universal Access Getting To XML With XHTML XHTML: • HTML represented in XML • Some small changes to HTML: Elements in lowercase <p> not <P> Attributes must be quoted <img src="logo" height="50"> Elements must be closed: <p >... </ p >) <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/> A joint CERLIM/UKOLN presentation 13 BK Universal Access CSS – Where You Define The Appearance HTML/XHTML should be used to describe the basis document structure CSS (Cascading Style Sheets): • Should be used to describe how documents should be used to describe how the document will be displayed • Separation of structure from appearance helps management (cf. modular programming) • Designed with accessibility in mind A joint CERLIM/UKOLN presentation 14 BK Universal Access W3C Standards - Conclusions W3C are coordinating the development of new open standards which: • Address the limitations of the original Web architecture • Are designed to provide device and application independence • Have accessibility considerations built-in from scratch • XHTML and CSS are the ideal now Let us now move away from standards and consider the people aspect A joint CERLIM/UKOLN presentation 15 JC Universal Access What is Accessibility? Ensuring systems and interfaces can be read by all users through: • Access to hardware and software • Use of appropriate assistive technology and accessibility features • Ensuring information can be interpreted by the technology i.e. design for all A joint CERLIM/UKOLN presentation 16 JC Universal Access Why Make Information Accessible? • Resources provided online • Growth of online learning, online tutorials, etc. • Inclusive society - widening access, information for all • Legislation e.g. Disability Discrimination Act, 1995; SENDA, 2001 A joint CERLIM/UKOLN presentation 17 JC Universal Access What Are The Benefits Of Universal Access? It helps people with ……….. • Visual impairments • Learning disabilities • Mobility impairments • Hearing impairments • Speech impairments • Seizure disorders (source: Burgstahler: Universal design of distance learning) A joint CERLIM/UKOLN presentation 18 JC Universal Access What Are The Benefits Of Universal Access? It also helps people who are …… • Using a PC with graphics switched off • Working in a noisy environment • Using a PC with a slow connection • Using other Web-based devices e.g. phones, PDAs, … A joint CERLIM/UKOLN presentation 19 JC Universal Access Accessible Web Design • Text descriptions for all images and sound • Contrasting colours • Plain fonts with adjustable font sizes • Properly labelled frames and tables • Alternatives for scripts, applets, plug-ins, etc. A joint CERLIM/UKOLN presentation 20 JC Universal Access Checking For Accessibility • WAI Guidelines and Quick Tips Checklist • Automated tools • Validation services • Web Audits and Policies • PEOPLE!!!!! A joint CERLIM/UKOLN presentation 21 Universal Access So Why Are People Important? • A Web site can comply with open standards. • A Web site can pass all the automated accessibility checks. • A Web site can appear to be accessible, BUT • An accessible Web site is not necessarily usable. • The best way to test for usability is by involving PEOPLE, i.e. the users A joint CERLIM/UKOLN presentation 22 JC Universal Access Usability Issues • Appropriate alternative text for images, links, etc. • Use of unambiguous language • Clear and consistent layout and labelling • Logical navigation of forms, search screens, etc. • Interactive elements: online chat, quizzes, new windows, pop-up windows, … A joint CERLIM/UKOLN presentation 23 JC Universal Access Checking For Usability • Automated checkers e.g. LynxView, Bobby, … • Ensure features can be altered e.g. font size, colours, etc. • Try pages with graphics turned off, different colours, etc. • Try pages using a number of Web browsers A joint CERLIM/UKOLN presentation 24 JC Universal Access Checking For Usability • Sample size ….. Don’t panic!!!! Ideally, try to use a sample of: • People with mixed abilities i.e. experienced, novice, visual impairment, hearing impairment, etc. • People using different assistive technologies A joint CERLIM/UKOLN presentation 25 JC Universal Access Checking For Usability • • • • Observation Transaction logging Verbal protocol Questionnaires and/or interviews A joint CERLIM/UKOLN presentation 26 JC Implementation Challenges Implementation Challenges We have: • Given an overview of the Web framework, the importance of standards, and the development of new, richer standards • Outlined the importance of a people-oriented approach to complement the technical architecture • Outlined basic design principles for usable and accessible Web services This sounds great in theory, but what around real-world deployment issues: • An accessibility & usability case study • Challenges at the institutional level A joint CERLIM/UKOLN presentation 27 JC Implementation Challenges Case Study: The NoVA Project NoVA: Non-visual access to the digital library: To develop understanding of the information seeking behaviour of blind and visually impaired people in Web-based digital library resources. A joint CERLIM/UKOLN presentation 28 JC Implementation Challenges NoVA Usability Testing • Sample of 20 ‘sighted’, 20 ‘visually impaired’ users. • Semi-structured tasks using four electronic resources. • Map search process together with verbal dialog. • Pre- and Post-task questions A joint CERLIM/UKOLN presentation 29 JC Implementation Challenges Examples Of Observations • • • • • • • Surveying page Time taken Types of mouse clicks and keystrokes Problems experienced Tackling problems Successful interaction Performance of assistive technologies A joint CERLIM/UKOLN presentation 30 JC Implementation Challenges Examples Of Usability Questions Navigation Searching Browsing Results Getting lost Other resources A joint CERLIM/UKOLN presentation 31 JC Implementation Challenges Conclusions Derived From NoVA Usability Testing • • • • Usability issues Design issues Training issues Software issues A joint CERLIM/UKOLN presentation 32 BK Implementation Challenges Implementation Challenges In the real world we are faced with several implementation challenges: • Deficiencies in specs, tools, etc. • Migration and support implications • Addressing user needs and resourcing implications and not just technical considerations A joint CERLIM/UKOLN presentation 33 BK Implementation Challenges 34 The Real World Web In the real world Web we need to recognise several external factors: • Due to the rapid development of Web specs ("the Web year") the specs themselves may be flawed, ambiguous or over-ambitious • Software has bugs (the cockup theory) • Software vendors have their own agendas (conspiracy theory) Together with local factors: • Inertia / unwillingness to act as guinea pigs • Licensing costs • Support issues • … A joint CERLIM/UKOLN presentation BK Implementation Challenges UK HEIs - A Case Study In Sept 2003 a survey of accessibility of 160+ UK HEI entry points was carried out: • Used Bobby tool (to report on problems which could be spotted using an automated tool) • How many WAI AA entry points were found? The survey found: • 4 entry points complied with WAI AA • One was a JavaScripted site (so isn't accessible) The UK HEI Web management community is aware of importance of accessibility and wants to implement accessibility. What are the difficulties? See <http://www.ariadne.ac.uk/issue33/web-watch/> A joint CERLIM/UKOLN presentation 35 BK UK HEIs - A Case Study (2) An example of a AA-approved site is the University of Bristol A joint CERLIM/UKOLN presentation 36 BK Implementation Challenges UK HEIs - A Case Study (3) Typical problems found: • Missing DOCTYPES • Missing ALT attributes in IMG tags • Use relative sizing and positioning (% values) rather than absolute (pixels) The first two problems could be fixed with little effort on a single page The third problem may conflict with usability criteria Let us now: • Look at the challenges in accessible Web sites (and not just pages) • Consider the usability issues A joint CERLIM/UKOLN presentation 37 BK Implementation Challenges WAI Implementation Challenges Many University Web managers want to comply with WAI but have encountered implementation challenges: • Limitations of authoring tools • Browser bugs (e.g. Netscape 4) • Apparent conflicts between usability and accessibility • Resource implications of deploying new tools, training, etc. • The scope of large institutional Web sites • Finding the funding A joint CERLIM/UKOLN presentation 38 BK Implementation Challenges WAI Implementation Challenges One Web manager commented that " I too have recently been struggling with just how rigorously the WAI guidelines should be implemented. … I certainly aspire to comply as fully as I can with the WAI guidelines but ": • Some guidelines are too theoretical • Will have a pragmatic approach: • Use tables for positioning • Will not associate form controls for search boxes • Not necessarily nest headers correctly A joint CERLIM/UKOLN presentation 39 BK Implementation Challenges Accessibility Policies You may wish to have an institutional accessibility policy All resources on the University Web site will comply with WAI AA But: • Is this practical • All Web sites? • What about MS Word / PowerPoint documents? • How will compliance be audited? • What about difficult areas (e.g. 3D maps)? • What about people? What about usability? • How will this be funded? • Is this policy intended to be rigorously enforced, or does it define an aspiration? A joint CERLIM/UKOLN presentation 40 BK Conclusions Standards • Use of open standards promises to provide a rich and platform- and application-independent framework which the HE sector needs • However deployment of standards-based services in a real-world context is not necessarily easy Accessibility • Technical aspects are an essential but not sufficient condition • Ensure that user issues are addressed • You should address usability issues alongside accessibility • There is probably a need for an accessibility institutional policy – but thought will be needed for this A joint CERLIM/UKOLN presentation 41 BK Advice and Good Practice • World Wide Web Consortium (W3C), Web Accessibility Initiative: <http:// www.w3.org/WAI/> • REVIEL Project - Good Design Principles: <http://www.cerlim.ac.uk/projects/ reviel/resource.htm> • Usable IT Web site: <http://www.useit.com/> • NoVA project final report: <http://www.cerlim.ac.uk/projects/ nova.html> A joint CERLIM/UKOLN presentation 42
