Transcript Introduction Lecture 1

Introduction
Lecture 1
CNET204 – Web Design with FrontPage
Winter 2009
Centennial College
Lecture 1 Outline
 What
is the Internet?
 Where did it come from?
 What are we going to discuss in
CNET204?
 Internet
 Physical Infrastructure
The Ever-changing Internet
Different colors based on IP address
http://research.lumeta.com/ches/map
What is the Internet?
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WWW
Video conferencing
ftp
telnet
Email
Instant messaging
…
A communication infrastructure
Usefulness is in exchanging information
“On-line interactive communities... will be communities not of
common location, but of common interest.... the total number
of users...will be large enough to support extensive general
purpose [computers]. All of these will be interconnected by
telecommunications channels... [to] constitute a labile network
of networks--ever changing in both content and configuration.”
J. C. R. Licklider
Where Did It Come From?
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It was invented by Madonna. JUST KIDDING!
Early 1960’s - DARPA (ARPA in 1960’s) project headed
by Licklider
Late 1960’s - ARPANET & research on packet switching
by Roberts
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First node installed by BBN at UCLA in September 1969
1969 - Four host computers (UCLA, SRI, UCSB, University of
Utah)
Get more info at:
http://www.isoc.org/internet/history/
http://www.packet.cc/internet.html
ARPANET, 1980
http://mappa.mundi.net/maps/maps_001/
History of the Internet
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1969 - RFCs begun by S. Crocker (http://rfc.sunsite.dk/)
1972 - Email by Ray Tomlinson & Larry Roberts
1970’s - TCP by Vint Cerf & Bob Kahn
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Evolved into TCP/IP, and UDP
1980s – Hardware Explosion (LANs, PCs, and
workstations)
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1983 – Ethernet by Metcalfe
DNS – Distributed and scalable mechanism for resolving
host names into IP addresses
 UC Berkeley implements TCP/IP into Unix BSD
 1985 – Internet used by researchers and developers
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History of the Internet
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Tim Berners-Lee at CERN in 1989
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Proposal for WWW in 1990
First web page on November 13, 1990
Hypertext - Text that contains links to other text.
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Ted Nelson’s Xanadu
Vannevar Bush’s Memex
(http://www.theatlantic.com/unbound/flashbks/computer/bushf.htm)
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W3C
Get more info at:
http://www.isoc.org/internet/history/
What will CNET204 cover?
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Simple to sophisticated web page creation
 Use of Adobe CS4
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Dreamweaver HTML and CSS editor
PhotoShop for images, pictures and layering
Flash for animations
Tables
 Layout Tables
 Cascading Style Sheets (CSS)
 Web Project done individually
Course Details
 Grading
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30% 4 assignments
30% Midterm
40% Final Project
All work must be posted to studentweb by the
due date
Lab Assignments
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Assignment #1
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Assignment #2
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Page with Image maps
Assignment #3
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Home Page
Tables
Layout Tables
Assignment #4
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Forms
CSS
Administrative Details
 Contacting
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staff
[email protected] 8230
http://facultyweb.centennialcollege.ca/bwarne
http://elms.centennialcollege.ca
 Communicate
through mycentennial
 Grading/testing online
 Students Rights and Responsibilties
Communicating Via the Internet
“Internet has made the information of the world as available as
information on a LAN”
• www.whatismyip.com
• www.wc3.org
• tracert
• ipconfig.exe
• www.visualroute.com
Performance: Latency and
Bandwidth
 Latency
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– ping command
How long minimum communication takes in
seconds (s)
Round trip vs. single trip
More difficult to overcome than bandwidth
 Bandwidth
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- http://pcpitstop.com
Number of bits per time unit usually seconds (bps)
bandwidth
link
latency
Ethernet
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Bob Metcalfe at Xerox PARC
Used for local area networks (LANs)
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Physically near one another
200 computers within 100 meters
Broadcast medium
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Single wire connects all computers
• Each computer has unique 48-bit MAC address
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All computers constantly listen
“Carrier Sense, Multiple Access with Collision
Detect”
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Sender waits until wire unused before sending
If hears collision, stops, waits random time,
retransmits