1. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 1 Web-Based Information Systems Dr. Osmar R. Zaïane University of Alberta Fall 2004 CMPUT 410: Internet and WWW

2. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 2 Web-Based Information Systems Perl & Cookies SGML / XML CORBA & SOAP Web Services Search Engines Recommender Syst. Web Mining Security Issues Selected Topics Course Content Introduction Internet and WWW Protocols HTML and beyond Animation & WWW CGI & HTML Forms Javascript Databases & WWW Dynamic Pages Preliminaries

3. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 3 Web-Based Information Systems Objectives of Lecture 2 Get a brief overview of the history of the Internet and the different tools that exist on the Internet; Understand the distinction between the Internet and the World-Wide Web. Internet and WWW

4. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 4 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

5. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 5 Web-Based Information Systems When Did It All Start? In 1945, Vannevar Bush wrote an article “As We May Think” describing a machine, Memex, containing human collective knowledge organized with “trails” linking materials of the same topic. The article revolutionized information technology before even the existence of modern computers.

6. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 6 Web-Based Information Systems Where is the memex? Memex is a hypothetical machine. The information stored ought to be accessible. We haven’t fulfilled the dream yet. But much has been achieved in 50 years.

7. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 7 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

8. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 8 Web-Based Information Systems Hypertext-Hyperlink-Hypermedia Following Memex idea, Ted Nelson developed the Xanadu project which aimed at placing the entire world’s literary corpus on-line. Ted Nelson coined the term hypertext in 1965. A document is not contiguous but is a set of connected parts of documents. Hyperlinks are links that connect sub- documents. Hypermedia is a multimedia hypertext document,

9. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 9 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

10. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 10 Web-Based Information Systems ARPAnet In the heart of the cold war, ARPA (Advanced Research Projects Agency) was created (1957). The purpose was to outrun the Russians in the race for mastering rocket launching. In 1969, it was decided to link sensitive computer centres by a network in order to withstand a possible nuclear attack. The idea was to allow centres to communicate even after a centre is destroyed. (Bob Taylor’s idea) It connected government labs, major research centres and universities. It existed until 1988 and was officially dismantled in 1990. Backbone Network speed: 64Kbits/second Major achievements: –TCP/IP, Domain Name Service, e-mail (SMTP), FTP, Telnet...

11. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 11 Web-Based Information Systems NSFnet DARPA, the Defense Advanced Research Projects Agency, still exists and the military have their own network but the original ARPAnet was integrated into the current Internet. The National Science Foundation in the USA funded the NSFnet which was created in 1985. Backbone Network speed: T1 (1.5mb/sec.) to T3 (45mb/sec.) It originally connected 5 major universities with supercomputer centres, but rapidly included other universities, research centres and private companies. Replaced ARPAnet as the backbone of Internet in 1990

12. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 12 Web-Based Information Systems What about the Internet? The Internet didn’t originate in the USA alone. Other networks existed in North America and Europe and other places in the world. BitNet, for instance, connected many research centres and universities. Bridges connected these networks to create a larger international network: the Internet. Late 90s: Internet2, funded by US universities, a sequel to NSFnet with new protocols.

13. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 13 Web-Based Information Systems Ca net 1990 1.5 mb/s NSFnet Ca net 2 1997 155 Mb/s Internet2 Ca net 3 1999 2.5 Gb/s Internet2 Abilene & vBSN projects CA net Year Speed USA equivalent Canada committed $110 million for Ca net4, a10 Gb/s optical network connecting research institutions across Canada.

14. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 14 Web-Based Information Systems Explosive Growth

15. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 15 Web-Based Information Systems 1973 First international connection (UK+Norway) 1970199519901985 1980 1975 1969 ARPANET commissioned by DoD 1974 TCP/IP 1979 USENET 1982 ARPANET transition to TCP/IP 1986 NSF-Net created 1990 ARPANET ceases to exist 1990 Archie 1988 IRC 2000 1991 Gopher 1991 WAIS 1992 WWW in CERN 1992 MBONE 1992 Veronica 1993 Mosaic 1993 Crawlers 1995 Java 1995 VRML 1994 E-commerce 1996 Internet phone 1972 ARPANET demonstration 1981 BITNET and CSNET come into being 1983 ARPANET splits into ARPANET and MILNET 1 1969 3 1973 11 1989 33 1991 49 1992 59 1993 81 1994 96 1995 134 1996 171 1997 # countries Year 4 1969 62 1974 313,000 1990 1,486,000 1993 6,642,000 1995 36,739,000 1998 # hosts Year 213 1981 1,961 1985 1994 UCSTRI 1993 Aliweb 1994 MLDB + WebQL 1991 Netfind 1994 Yahoo 1985 FTP 1997 Wireless Internet access 1998 Internet Tax Freedom Act 1996 AltaVista 1986 NNTP 1999 Internet2 NGI 1999 RSVP 1994 Harvest 1996 WebSQL 1997 WebOQL 1998 Google 1998 Clever 1993 W3C 1971 FTP on NCP Internet Timeline

16. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 16 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

17. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 17 Web-Based Information Systems Advent of the World-Wide Web In 1990, Tim Berners-Lee developed a on-line hypertext- based system to help researchers at CERN in Switzerland share information across a diverse computer network. He came up with first versions of HTML (based on SGML) and the HTTP protocol. HTTP and HTML catapulted the Internet to new heights. The WWW revolutionized the use of the Internet thanks to a multimedia user friendly interface: a web browser. Mosaic was developed in NCSA by students at the University of Illinois in 1993, among them Marc Andreessen who created Netscape in 1995.

18. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 18 Web-Based Information Systems The WWW is not alone There are other tools on the Internet. They could be classified as: –Command Line. Ex: FTP (1971) –Menu-based. Ex: gopher (1991) –Search engine. Ex: WAIS (1991) –Hypermedia. Ex: WWW (1991)

19. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 19 Web-Based Information Systems Other Taxonomy of Internet Tools Communication services –E-mail, newsgroups (usenet), telnet, internet relay chat (IRC), … Information storage and exchange –FTP, Gopher, Alex, … Information Indexing –Archie, Veronica, Wais, UCSTRI, Whois, … Interactive Multimedia information delivery –WWW and its indexes.

20. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 20 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

21. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 21 Web-Based Information Systems Client-Server Architecture The World-Wide Web is an assortment of interconnected computers. In this context, computers provide data to other computers. Provides the information Requests the information Server Client

22. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 22 Web-Based Information Systems Client-Server Architecture Request Response URL HTML page Server Client HTTP

23. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 23 Web-Based Information Systems Client-Server Architecture Request + Data Response HTTP DB HTTP server Browser Application CGI + Servlets (Perl and Java) Javascript and Java

24. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 24 Web-Based Information Systems Application / Application Communication – scenario 1 Request + Data Response HTTP DB HTTP server No browser involved Application Identifying fields and variables Application Parses the HTML page to extract the needed information Wrapper needed Wrapper needed

25. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 25 Web-Based Information Systems Application / Application Communication – scenario 2: XML request + Data Response HTTP DB HTTP server CORBA can also be used to exchange objects Application parses XML with known DTD or schema SOAP over XML doc XML doc Web Service

26. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 26 Web-Based Information Systems Outline of Lecture 2 The Memex machine: the dream will come true Hypertext: linking new kinds of documents The Internet: infallible information exchange The World-Wide Web and the start of a new era Web-based applications Some terminology

27. University of Alberta  Dr. Osmar R. Zaïane, 2001-2004 27 Web-Based Information Systems Terms in the Glossary Internet: group of networks connected together. The Internet refers to the global connection of networks around the world. LAN: Local Area Network: a group of computers, usually all in the same room or building, connected for the purpose of sharing files, exchanging email, and collaboration. Intranet: internal company network. Internal use of web capabilities. Extranet: ability to securely connecting the intranet with defined external networks. CGI: Common Gateway Interface: means of developing application for the web on the server side. Middleware: a tier usually between a web application or a web server and a database or another application layer.