Web Engineering Class 3

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Web EngineeringClass 3

• 2005/10/18
• Jacek Kopecký
• jacek.kopecky_at_deri.org

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Homework

• Feedback, scores late
• In feedback email I use first name
• Let me know if I get it wrong
• A few comments here
• On content
• On style

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Homework CommentsContent

• Problem finding favorite site?
• Welcome page in browser a good candidate
• Essay not so much about what the site does
• Instead how it does it
• Wanted both good and bad things
• Makes you think more
• Many forgot what can I do to change this?
• The others should send those emails anybody?
• Bigger chance on sites that you need to use
• Other ways?

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Homework CommentsStyle

• In HTML, links should be links
• Watch the line breaks
• Funny English not an evaluation criterion
• As long as its somewhat understandable
• Major things pointed out in personal responses

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Overview of Class 3

• Various stages of the web
• Networks, ISPs
• Homepages, blogs, wikis
• Search engines, directories, portals
• Interactive content applets, DHTML, AJAX
• Peer-to-peer, push technology
• .com bubble

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Why Stages?

• Test-and-error evolution
• Learning what works and whats useful
• Different people coming in
• With different uses, requirements, expectations
• Replacing old technologies, ideas

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Stages Crazes Areas

• Network companies
• Pre-web networks, ISPs, portals
• Content
• Community news-sites, wikis, portals
• Company presentations
• Personal homepages, blogs
• Interactive content
• Applets, scripts, AJAX
• Chat rooms

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Stages Crazes Areas contd

• Finding information
• Directories, search engines
• Technology hypes
• Push
• Peer-to-peer
• Syndication
• Mobile web
• Web Services
• Dot-com bubble

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Web Stages and CrazesNetwork Companies
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Older Commercial Networks

• CompuServe
• Prodigy
• America Online
• Closed worlds
• Internal content, specialized client software
• Mailing, chatting capabilities
• Forced to add gates to ARPAnet
• Mostly evolved into ISPs

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Internet Access Providers

• Standardized, independent services
• Email, IRC, Usenet
• Web, instant messaging, games
• Only connectivity, no own content or services
• Apart from company presentation, tech support
• Small, local, cheap
• Metered vs. flat-rate access
• Usually called ISPs
• IAP used here for the distinction

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Hosting Providers

• Your content on their server
• Your server on their network
• You must trust them
• Often together with email service
• May offer web design services

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Internet Service Providers

• Integrating IAPs hosting
• More expensive, with benefits
• Email accounts, web hosting included
• Own content, services
• Often evolving into a big portal
• But AOL split into 4 units
• Audience, Access, Digital Services, AOL Europe

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Web Stages and Crazes Network Companies
Conclusions

• Tying independent products not good
• Access
• Content
• Services
• Examples
• Customers of other IAPs can also be customers of
  your content portal
• Customers of other web hosting companies can also
  be your web design customers
• Initially rich content was important for ISPs

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Web Stages and CrazesWeb Content
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Beginnings in CERN

• Sharing scientific information
• Data accessibility
• Physics experiments generate lots of data
• Information interconnection
• Linking papers to data, data to institutes
• Listing related papers, organizations, people
• Originally, a single trusted community

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Homepages

• Showing Im also already here!
• Everybody needed web presence
• Problem with updates
• Being replaced by specialized sites
• Pictures in photo album sites
• News or writings on blogs
• Personal info on address book sites
• Free or cheap services exist for all of that
• Homepages now mostly funny memories

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Community Sites

• Web grew too big
• Single site on a topic, usually amateurs
• Initially directories, information collections
• Straight evolution to community news
• On the Web, news means new links
• User contribution
• Articles, comments need for moderation
• Often web-based user messaging
• Good credibility, trust
• Many dot-com startups, some survive

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Wikis

• Shared document authoring system
• Earlier travel guides, H2G2
• Not using HTML for authoring
• Very simple formatting, linking syntax
• Allowing non-computer people to contribute
• Usually trusted intranet knowledge bases
• Wikipedia.org
• Useful and fairly reliable

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Portals

• Lot of own content, services
• News content, user discussions
• Also knowledge base, entertainment
• Aggregation of smaller content/service providers
• Origins
• A community smaller portals
• A search engine or directory big ones
• Big portals aim to be your home
• What portals do you use?

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Commercial Presentations

• About a product or a company
• Boom during dot-com era
• Before that, you had the telephone book
• Good source of income for students
• Predictable structure
• Advertisement standard of credibility
• Adding on-line selling, free SW trials

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Blogs

• Originally Web Log
• Diary, dynamic homepage, news/idea stream
• People who have something to say
• But also company blogs
• All ranges of topics and writing styles
• A lot of referencing, linking, trackback
• Initially, a lot of blogging about blogging
• Companies encourage blogging
• SUN, IBM, Microsoft, Google etc.
• Legal issues

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Blogs contd

• Highly fluid landscape
• Blogs come and go, get abandoned
• Better than homepages
• No need to update old material
• Syndication/aggregation
• Many special SW packages and sites
• MovableType, Bloglines
• Many client-side reader programs
• Do you read any blogs? Have blogs?

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Web Stages and Crazes Web Content Summary

• Personal homepages
• Appeared, disappeared, reappeared as blogs
• Company, product presentations
• Unknown before dot-coms, now taken for granted
• Big and small community sites
• For real and virtual communities
• Any common ground is good enough

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Web Stages and Crazes Web Content Conclusions

• New, interesting styles of publishing
• Aggregation, syndication
• Integration of several functions
• News
• Discussions
• Information bases
• Sites consciously specifically targeted
• Building/serving a community
• Varying levels of trust

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Web Stages and Crazes Interactive Content
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Applets

• HTML with animated pictures still too static
• Why not embed a program?
• Java Applets, ActiveX
• Unclear intention, mostly eye-candy
• Support, performance problems
• Now only specialized demonstrations
• The real question why embed a program?
• Flash almost just a better form of animated GIF

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JavaScript

• DHTML Dynamic HTML
• Client-side scripts
• Can affect the page
• Limited interactivity
• Better look and feel
• Interoperability issues
• Less of a phenomenon than applets
• But more useful

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AJAX

• Asynchronous Javascript And XML
• Full interactivity
• Much better feel
• Still interoperability issues
• New style of applications
• Google maps
• Flickr
• Netvibes
• Same idea as forms, better UI

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Chat Rooms, Message Boards

• Varying uses of applets, JavaScript
• Replacing IRC
• User-friendly web interface
• Phenomenon for the young
• Appealing to young newcomers to web
• Little credibility, trust

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Web Stages and Crazes Interactive Content
Conclusions

• Initial over-use of new technologies
• Too much will drive customers away
• Recreation of non-web things on the Web
• Enabled mostly by JavaScript, AJAX
• IRC, also games, messaging
• Not new paradigms

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Web Stages and Crazes Finding Information
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Directories

• Natural concept
• Initially, one page listed all web servers
• Most well-known Yahoo!
• Manageability vs. reach (scalability)
• Adding new links, checking the old ones
• Too many levels or too many links on one level
• Small, specialized directories make sense
• Full-text search proved better
• Internet directories evolved or died

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Search Engines

• Simple full-text search
• Ranking algorithms
• Including paid rankings
• Up to six engines used for the same search
• Big innovation brought by Google
• Huge crawling, indexing systems
• Necessity for big ISPs, big sites

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Web Stages and Crazes Finding Information
Conclusions

• Form of search depends on the scale
• Web is big
• Google most successful
• Sub-webs need not be so big
• Specialized directories may be better
• Requirement only a limited number of results
• Users get easily overloaded

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Web Stages and Crazes Technology Hypes
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Push Technology

• Web doesnt scale for information delivery
• PointCast (and others) push information
• Mostly news, entertainment like TV
• Soon used for pushing advertisement
• Evolved later into pop-up ads
• Delivery problem partly solved by syndication
• Web remains pull-based
• Push technology in use where appropriate

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Peer-to-peer Technology

• Content distribution and communication
• Opposed to client-server model
• Complementing, not replacing the web
• Also used in grid computing
• Self-organization, failure resistance
• Napster not pure peer-to-peer
• Uses direct connection but one central server
• Distributed resource availability
• Bittorrent
• Fine-grained distributed bandwidth

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Mobile Web

• Everybody has a cell phone
• Specialized mobile web WAP ( WML)
• Devices no longer so limited
• Users will rather wait than be limited
• WAP died early
• Mobile web now extends normal web
• Location-aware services

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Aggregation, Syndication

• Combining data from different sources
• Or sending data to different outlets
• Periodic polling
• Mostly news and blog feeds
• Atom, RSS the common formats
• Keeping up with updates
• Frequent polling is costly space for push tech
• Trade-off convenience vs. efficiency
• Enables reading more blogs, news

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Semantic Web

• Computers should understand information
• Reasoning getting to implicit conclusions
• Annotated data
• Searching according to metadata
• Semantically represented data
• Reasoning over web database
• Fewer formats (only logics, ontologies)
• Fewer implementations (only reasoners)
• Easier data/function integration

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Semantic Web Issues

• Reasoning is expensive
• Few (if any) useful reasoners available
• Limiting available information
• Not reasoning over the whole Web
• User interface, presentation
• Security, trust
• Hype since 1994, going the way of AI
• Producing useful results but not the high goal

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Web Services

• Distributed computing
• RPC technology not good for Web
• Using XML, web protocols
• Great promise undelivered
• Millions of publicly available services in
  2002!
• Web Services useful in integration
• Still open potential
• Semantic Web Services?

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Dot-com Bubble

• Investment in anything internet-related
• Fragile business model
• Building market/mind share
• Then trying to make money on it
• Big investments, IPOs
• Burst in 2000, 2001
• Some meaningful businesses survived
• Rest is dot-compost

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Web Stages and Crazes Technology Hypes
Conclusions

• Watch these technologies
• See through the hype!
• Apply whats useful
• Wait with the investment money
• But cash in on ideas

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Overall Conclusions

• Stages and crazes test innovation
• Be ready for a change again
• Mind your community
• Take scale into consideration
• Especially growing scale
• Test your novel ideas against history

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Next Class

• Web Architecture (AWWW document)
• Representational State Transfer REST
• Uniform Resource Identifiers URIs
• Interesting W3C TAG issues

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Homework

• What is going to be the next craze?
• Describe the new technology
• Provide plausible reasons for its boom
• Technical, psychological, sociological
• New paradigms, society changes
• Dont be too negative
• Moderate sci-fi is welcome