The Latest Web Developments

1
The Latest Web Developments

• Brian Kelly
• UK Web Focus
• UKOLN
• University of Bath
• B.Kelly_at_ukoln.ac.uk
• http//www.ukoln.ac.uk/

2
Contents

• Introduction
• Data Formats
• HTML, CSS
• XML
• Transport Protocols
• HTTP
• Metadata
• Technology and Society
• Conclusions

3
UK Web Focus

• UK Web Focus
• National web coordination post for UK HE
  community
• Based at UKOLN, University of Bath
• Responsibilities include
• Technology watch
• Information dissemination in variety of ways
• Workshops (national, regional)
• Presentations at conferences and seminars
• Online
• Coordination activities
• Representing JISC on W3C
• Brian Kelly appointed on 1st November 1996
• Involved with web since January 1993
• Previously worked at University of Newcastle,
  Leeds, Liverpool, and Loughborough

4
HTML 4.0

• HTML 4.0
• Proposal currently under review
• Includes
• Advanced Forms
• Frame Improvements
• Table Enhancements
• Object Support, Script and Style Elements
• Addresses accessibility and internationalisation
  issues
• Concerned with document structure - layout
  addressed by related style sheet proposal
• See http//www.w3.org/Press/HTML4

5
CSS

• CSS1 recommendation agreed in December 1996
• CSS 2 draft released in August 1997. Includes
• Font support
• Positioning of HTML elements
• Printing Extensions (page breaks, multiple media,
  etc)
• Aural Cascading Style Sheets for visually
  impaired, in-car use, etc.H1 pause
  20msP.part.romeo voice-family romeo,
  maleP.part.juliet voice-family juliet,
  female

Filters
6
CSS

• Web services using style sheets are already being
  developed

lthtmlgt ltStylegt .channeltext font 32pt
verdana font-weight bold text-decoration
none color black .tstext font 10pt
verdana font-weight bold text-decoration
none color black
7
DOM

• Document Object Model
• Known as DOM
• Platform- and language-neutral interface that
  will allow programs and scripts to dynamically
  access content, structure and style of documents
• Cf. Dynamic HTML
• See http//www.w3.org/MarkUp/DOM/

8
Maths

• MML (Mathematical Markup Language) draft is
  available
• An XML application
• Renderers available (e.g. WebEQ Java application)
• See http//www.w3.org/Math/

9
HTML Limitations

• Problems with HTML
• Introduction of new tags via standardisation
  route takes too long
• Introduction of new tags by browser vendors is
  controversial (ltBLINKgt) and can cause problems
  with interworking
• Many potential tags aren't appropriate for
  standardisation (ltSTAFF-NUMgt, ltHYDROGENgt)
• These issues are being addressed by XML
  (eXtensible Markup Language)

10
XML

• XML
• A meta-langauge
• A simple dialect of SGML designed for the Web
• Design goals
• straightforwardly usable over the Internet
• support a wide variety of applications
• compatible with SGML
• easy to write programs which process XML
  documents
• documents should be human-legible and reasonably
  clear

lt?XML VERSION"1.0" RMD"NONE"?gt ltFAQgt ltQgtltIMAGE
XML-LINK"ques.gif"/gtCan I create my own XML
documents without a DTD?lt/Qgt ltAgtYes. This is an
example of a well-formed document, which can be
parsed by any XML-compliant parser. However, it
won't know how to display it unless you supply a
stylesheet.lt/Agt lt/FAQgt
11
XML Applications

• XML is already being proposed for a variety of
  applications
• MML (Math Markup Language)
• CML (Chemical Markup Language)
• CDF (Channel Definition Format)
• MCF (Meta Content Format)
• OSD (Open Software Description)
• Web Collections
• ...

12
HTTP Developments

• HTTP/1.1
• Addresses problems in HTTP/1.0
• Single resource fetched per request
• Poor caching model
• Performance
• Lack of extensibility
• See http//www.ics.uci.edu/pub/ietf/http/
• HTTP/NG
• Reengineering of protocol architecture
• Characterization of the current use of Web
• Multiple transports (realtime and multicast,
  transport level compression, Firewalls,
  tunneling, and security, ...)

13
PICS

• PICS
• Platform for Internet Content Selection
• Developed in response to US Communications
  Decency Act (CDA)
• Set of standards that facilitate
• Self-rating (content providers can label their
  content)
• Third-party rating (independent labeling
  services)
• Ease-of-use (parents and teachers can use
  ratings)
• See http//www.w3.org/PICS/
• Developments
• Following acceptance
• Changes in US legislation
• Recognition that ratings are a form of metadata

14
PICS/NG and RDF

• PICS/NG
• Proposal for next generation of PICS
• Support for string values
• For use with digital signatures and assertions
  (this resource really is from the University of
  Ambridge, and it is a legally binding description
  of courses)
• RDF
• Resource Description Framework
• Based on XML
• Replacement for PICS/NG
• Early stages

15
Metadata Requirements

• Imagine a University prospectus

A Metadata Coordination Group has been set up to
coordinate these activities
16
Metadata Architecture

• Metadata - the missing architectural component
  from the initial implementation of the web

URLs, URIs, URNs
AddressingURL
MetadataRDF, PICS, TCN, DSig, DC,...
TransportHTTP
Data formatHTML
HTML 4.0, CSS, XML
HTTP/1.1, HTTP/NG
17
Technology and Society

• WAI
• Web Accessibility Initiative
• Aims to make Web formats and protocols more
  accessible to people with disability
• See http//www.w3.org/WAI/
• P3
• Platform for Privacy Preferences Project
• Enable computer users to be informed about use of
  their personal data
• Proposals include Open Profiling Standard (from
  Netscape, Firefly Verisign) and Privacy and
  Profiling on the Web (from Microsoft)
• See http//www.w3.org/P3/Overview.html

18
Conclusions

• Web protocols are still being developed
• Software vendors seem to be now supporting
  development of Web standard
• Service providers may find chasing new
  developments expensive
• There is a need for a clear understanding of
  architectural developments