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Future Technologies: Deployment Issues Brian Kelly UK Web Focus UKOLN University of Bath Email Address [email protected] URL http://www.ukoln.ac.uk/ UKOLN is funded by the Library and Information Commission, the Joint Information Systems Committee of the Higher Education Funding Councils, as well as by project funding from the JISC’s Electronic Libraries Programme and the European Union. UKOLN also receives support from the University of Bath where it is based. 1 Contents • Introduction • Barriers to Deployment • Revisiting Data Formats: • HTML and XHTML • CSS • Where Are We: Four Case Studies • • • • 2 • • • • • Entry Points Search Engines 404 error messages Web Gateways Metadata Browser Issues Content Management Systems Deployment Issues Conclusions Aims of Talk • To consider barriers to deployment of new technologies • To address implementation models for new technologies • To look at case studies in a number of areas Barriers to Deployment What barriers can you think of? 3 Your Concerns I know that CSS, XML, HTTP/1.1, RDF, etc. are good ideas. But: • I don't want to be at the leading edge • I want to be at the leading edge and have to convince by boss • I want to stick with the Web circa 1996 • We've only got Netscape 3 browsers • You can't do much in FrontPage 97 4 The Scale of the Problem Note: Analysis aborted after 15,315 pages Off-site links not checked Analysis files over 160Mb 5 HTML XHMTL XHTML: • Future-proofs your HTML • Has beneficial side-effects: <p>closed papa</p> - CSS rendered correctly • Example of why you need valid HTML resources Deployment: • • • • Much XHTML support provided by authoring tools <br / > is a problem Problem with vi, Notepad, etc. Tidy utility for retrospective conversion – see <http://www.w3.org/People/Raggett/tidy/> Caveats: • Still a Proposed Recommendation 6 HTML CSS CSS: • Preferred way of defining document appearance Problems: • Netscape has very poor support of CSS • Netscape and IE have incomplete support Deployment: • Should be used today • For manually-created CSS consult list of safe CSS at <http://www.webreview.com/guides/style/> • Modern authoring tools may produce safe CSS • User-agent negotiation may be used • See also Core Style Sheets at <http://www.w3.org/StyleSheets/Core/> 7 Case Studies "It can be dangerous and expensive to be at the leading edge. There are also dangers in being left behind" How is the UK HE community addressing: • • • • 8 Institutional Home Page Searching institutional web service 404 error messages Web gateways Case Study 1: Home Page View a tour of Yorkshire University home pages at <http://www.ukoln.ac.uk/web-focus/events/ seminars/brad-web2000/web-tour/>. What do you notice? How does Bradford compare? 9 Case Study 2: Searching View a tour of Yorkshire University search interfaces at <http://www.ukoln.ac.uk/web-focus/events/ seminars/brad-web2000/web-tour-search/>. 10 Case Study 3: Gateways View a tour of Yorkshire University web gateways at <http://www.ukoln.ac.uk/web-focus/events/ seminars/brad-web2000/web-tour-gateway/>. 11 Case Study 4: Home Page View a tour of Yorkshire University home pages at <http://www.ukoln.ac.uk/web-focus/events/ seminars/brad-web2000/web-tour-404/>. 12 Workshop "Institutional Web Management: The Next Steps" workshop: • Held at Goldsmith College on 7-9 Sept 99 • Third in series of annual events aimed at institutional web managers • Key themes: – – – – – Resourcing (John Slater), Personalisation (Joe Passmore, Ulster) E-Business (David Christmas, OU) Content Management (Stephen Emmott, KCL and others) Multimedia (Greg Newton-Ingham [UEA] and Michael Wilson, RAL) • See workshop report (and links to materials) at <http://www.ariadne.ac.uk/issue21/ web-focus/> 13 Metadata Metadata: Structured information for use by applications HTML: Unstructured information for viewing by people Metadata is growing in importance: • Resource discovery • Web site administration • B2B (business to business) applications Dublin Core: • Standard for resource discovery metadata • Not yet supported by search engine vendors • Growing importance in specific communities (e.g. UK HE for national searching, HE Mall?) • Metadata management an issue 14 Metadata Example The Exploit Interactive web magazine uses Dublin Core metadata to provide enhanced searching locally. The metadata can also be used by third party applications http://www.exploit-lib.org/ 15 You are unlikely to be motivated to use metadata (for example) unless there is are clear benefits. This enhanced search service will encourage information providers to provide the metadata Metadata Example (2) Exploit Interactive uses ASP to manage server-side includes. As well as including standard navigational aids, the SSIs transform the metadata article.asp Title="foo" Description ="xxx" .. <! include dc-metadata.ssi)> <! include article.htm> .. <! include footer.ssi)> dc-metadata.ssi <meta content="DC.description" value = "<%=description %>" <meta content="description" value = "<%=description %>" article.htm Stored in neutral format, which helps reuse Storing metadata in neutral format and transforming it will enable it be transformed into new formats (e.g. RDF) 16 Browser Issues The web was designed to be evolvable and backwards compatible Unfortunately this isn't the case, due to: • Proprietary extensions which do not coexist with standards • Authoring tools which make it easy to propagate proprietary extensions and poor markup (cf. MS Word) • Pace of web development • Browser bugs • Difficulties in getting rid of (flawed) old browsers 17 Browser Issues Issues: • Should organisations adopt a browser management policy (cf. operating systems, word processors, etc.)? • Which browser / browser version to choose? • What about specialist browsers (PDAs, Lynx, Opera, etc)? • Need for browser management kit to minimise maintenance Talk by Brett Burridge on this topic. See <http://www.ukoln.ac.uk/web-focus/events/ workshops/webmaster-sep1999/materials/ browser-management/> 18 Browser Issues Even with a browser policy, you still have to consider support for other browsers (esp. for public web site): Client-Side Browser sniffing: • Javascript in all HTML pages • Maintenance problem Server-Side Browser sniffing: • In server-side language (e.g. ASP / PHP/FI) • Could be used to deliver safe CSS (e.g. see <www.disinhe.ac.uk> in Netscape and IE) Protocol Developments: • Support for PDAs, WebTVs, etc • Transparent Content Negotiation and CC/PP • One for the future 19 Content Management Systems Approaches such as external CSS files, SSI for managing reusable fragment, etc. are useful But: • Still a file-oriented view • Help manage a web site aimed at human use • May be difficult to manage server and client-side code Content management systems • May have a database or object-oriented view • May help manage a web site which can be repurposed • Likely to have backend XML data store and use XSL to transform to HTML / CSS 20 Deployment Issues More sophisticated deployment techniques can be adopted to overcome deficiencies in simple model Original Model Web server HTML resource browser Sophisticated Model Backend processing HTML / XML / database resource Intelligent Web server Is it time to move on from using authoring tools to manage files to content managements systems which manage objects and enable resources to be repurposed? 21 Web server simply sends file to client File contains redundant information (for old browsers) plus client interrogation support Client proxy browser Server proxy Cultural Issues University "culture" may influence directions of web developments How did you address need for Help Desk tracking software: • Make decisions internally or liase with other institutions? • Buy an off-the-shelf shrink-wrapped package • Write an MS Access database application • Take a C compiler and Linux server 22 What Next For Bradford? Conservative Stay as you are. If so, make this a deliberate approach, and be aware of strength and weaknesses Change (1) Introduce new innovations. Make use of offthe-shelf solutions What should you do next? A Fourth Way Are there alternative approaches? 23 Change (2) Introduce new innovations. Make use of open source solutions and home-grown approaches Collaboration You can't do it all on your own Events: Mailing lists: web-support website-info-mgt … Working Together Annual Institutional Web Management workshops … Regional Events: Yorkshire (and beyond?) events? JISC: JTAP projects and reports JISC reports Other Institutions: Relevant web resources 24 Conclusions To conclude: • Standards are important • Implementation requires much thought • More sophisticated architectures can help avoid human errors in managing web sites • You will need to decide on an open-sources vs. shrink-wrapped solution • You can't to it all on your own 25