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Lecture 19: Internet Intro to IT
COSC1078 Introduction to Information Technology
Lecture 19
InternetJames Harland
Lecture 19: Internet Intro to IT
Introduction to IT
1-4 Introduction, Images, Audio, Video
5-6 Computer Fundamentals Assignment 1, WebLearn Test 1
7 Review
8 Operating Systems WebLearn Test 2
9 Operating Systems Assignment 2
10 Survey & Internet
11 Internet Security WebLearn Test 3
12 Future of IT Assignment 3, Peer and Self Assessment
Lecture 19: Internet Intro to IT
Survey
Who is this?
Cecily Walker
Teaching and Learning Advisor
10.10.1
Lecture 19: Internet Intro to IT
Overview
Survey
Questions?
Assignment 3
Internet
Questions?
Lecture 19: Internet Intro to IT
Assignment 3
Review
(re-) answer What is IT? questions from Tutorial 1
Identify difficult parts of the course
Suggest new questions
Include favourites from Assignments 1 and 2
Reflect
Answer reflection questions from tutorials
Research
Write about a particular IT topic of your choice (5-6 paragraphs)
Lecture 19: Internet: Images Intro to IT
Internet
Worldwide publically
accessible network of
(millions of)
interconnected
computer networks
which carry information
and provide services
Lecture 19: Internet: Images Intro to IT
Internet
Lecture 19: Internet: Images Intro to IT
Internet
Lecture 19: Internet: Images Intro to IT
Internet
Lecture 19: Internet: Images Intro to IT
Communications Developments ????: Writing 1440: Printing press 1844: Telegraph 1877: Telephone 1919: Radio 1928: Television 1969: ARPANET (Advanced Research Projects Agency) 1970's: Internet Protocol (IP) 1984: Domain names (.com, .org, etc) 1991: World Wide Web ....
Lecture 19: Internet: Images Intro to IT
Number of Internet Hosts
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
0
100000
200000
300000
400000
500000
600000
Internet
Originally designed to survive nuclear war
Grew out of army research into missile communication
Key role in breaking down the Berlin Wall
Lecture 5: Internet Intro to IT
Internet
Dedicated channel:
two nodes exclusively use a single channel
works like traditional telephone
Packet switching:
break data down into packets
send packets from many users along link
can exploit redundancies and variations in network
Lecture 5: Internet Intro to IT
Protocols
Transmission Control Protocol (TCP):
basic necessities for data transfer
connection-oriented
Internet Protocol (IP):
data-oriented
necessary for packet-switched network
“Should run on two tin cans and a string”
There is an implementation for carrier pigeons ...
Lecture 5: Internet Intro to IT
Protocols
Lecture 5: Internet Intro to IT
Application Protocols
Define messages sent and data formats used
Generally known by user
Examples include HTTP, HTTPS, FTP, etc.
Often specified in resource identifiers
http://www.mysite.com:8080/info/mypage.htmlhttp://www.mysite.com:8080/info/mypage.htmlhttp://www.mysite.com:8080/info/mypage.htmlhttp://www.mysite.com:8080/info/mypage.html
Lecture 5: Internet Intro to IT
World Wide Web (WWW)
Combination of 4 different ideas:
Hypertext: information format for moving documents around
Markup Language: codes embedded in text indicating structure and presentation meaning
Resource Identifiers (URI, URL, ...)
Client-server model: client software requests resources from servers
Lecture 5: Internet Intro to IT
Internet Uses
File transfer & remote services
Instant messaging
Web browsing
Peer to peer (P2P)
Telephony
Streaming media
“Web 2.0”
....
Lecture 19: Internet Intro to IT
Conclusion
Work on Assignment 3
Name 5 people who are unaffected by the Internet …
