Transcript Exploring the Internet

Exploring the Internet
Week 1
LBSC 690
Information Technology
Agenda
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Why study information technology?
Teaching Theater orientation
Course description and syllabus
Seven uses of the Internet
Computing at Maryland
Teaching Theater Introduction
• Logging on (account name doXX)
– Choosing a password
• Windows navigation
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Double click
Drag and drop
Size widgets
Close button
Teaching Theater Introduction
• Internet Explorer for class web page
– http://www.clis.umd.edu/courses/690/
• Microsoft Word for class notes
– Get my outline notes from class directory
– Save your notes in your personal directory
• Powerpoint for class slides
• Photos
Course Goals
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Understand computers and networks
Learn to use common software tools
Evaluate the role of information technology
Solve a practical problem
Develop a personal plan for further study
Instructional Approach
• Readings
– Provide background and detail
• Class sessions
– Provide conceptual structure
• Electronic outline provided in class
• Slides and videotapes available
• Homework, lab sessions, project
– Provide hands-on experience
Syllabus
• Master the tools in the first 7 weeks
– Internet, word processors, spreadsheets,
databases, programming, security
– 2 readings and 1 homework each week
• Apply the tools for the last 7 weeks
– Group work, library automation, educational
computing, social issues, digital libraries
– 2 readings each week and the term project
Course Materials
• Textbook
– Oakman, The Computer Triangle, 2nd edition
• Supplemental readings
– Course packet available from IDSC
• Daily access to a networked computer!
• A few 3.5 inch floppy disks
• Book on Microsoft Office (optional)
Grading
• 45% individual work: midterm and final
– 30% for the best, 15% for the other
• 40% group work: project in 3 person teams
– 30% for the project, 10% for the documentation
• 15% at your option: homework
– 3% each for best 5 of the 6 assignments
– Can work together, but write it up separately
Example LBSC 690 Grades
Final Score (Excess 75)
25
20
Score-75
15
10
5
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
Rank (higher better)
Observations on Grading
• Exam scores are very important
– One exam is worth up to 10 homeworks
– Midterm grades predict final grades well
– Moral: Use the homework to learn the material
• Little things can make a B into an A
– less than 1 point typically separates B+ and A-
The Fine Print
• Group work is encouraged on homework
– But you must personally write what you turn in
• Deadlines are firm and sharp
– Allowances for individual circumstances are
included in the grading computation
• Academic integrity is a serious matter
– No group work during the exams!
– Don’t discuss exam until everyone has taken it
Breaks
• 10 minute break after the first hour
• 5 minute break after the second hour
• No sodas or food in the teaching theater
• Please have your picture taken today
Seven Uses of the Internet
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Web pages
File Transfer Program (FTP)
Telnet
Electronic mail (email)
Newsgroups (Usenet)
Talk
Chat
Describing Internet Applications
• Who participates?
– Computer-to-computer or person-to-person
• For computer-to-computer:
– One-way or two-way?
– Authenticated or unauthenticated?
• For person-to-person:
– One-to-one or many-to-many?
– Synchronous or asynchronous?
Web Pages
• Computer-computer, one-way, unauthenticated
– Two-way and authenticated variants exist
• Viewed using a browser
– Netscape, Internet Explorer, Lynx
• Uniform Resource Locators (URL)
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Protocol
Machine
Port
Path
File
http: (or ftp: or file:)
//www.clis.umd.edu
:80 (optional if port 80)
/courses/690/ (case sensitive)
Welcome.html (optional if standard)
Finding Web Pages
• Bookmarks
– Useful if you have been there before
• Directories (http://www.yahoo.com)
– Access by category
• Limited to things processed by hand
• Search engines (http://altavista.com)
– Access by content
• Broad coverage, but lots more trash
File Transfer Program (FTP)
• Computer-computer, two-way, authenticated
– Anonymous FTP is an unauthenticated version
• Use userid “anonymous”, your email is password
• Multiple interfaces
– Web browsers, command line, FTP programs
• Used to move files between machines
– Better than carrying a floppy disk around
– Use FTP to download your class notes at home
• ftp ttclass.umd.edu
Visualizing FTP
telnet wam.umd.edu
(login as oard)
cd ../pub
ls
cd 690
wam.umd.edu
logged in as
oard
hawk.umd.edu
logged in as
anonymous
ls
ftp hawk.umd.edu
(login as anonymous)
pub/
home/
incoming/
pub/
ls
cd pub
396/ 690/ 708a/
ls
get demo.txt
quit
demo.txt
demo.txt test/ javascript/
Telnet
• Computer-computer, two-way, authenticated
– Web pages and FTP send one file at a time
– Telnet sends one character at a time
• Simulates a dial-up connection
– Use telnet to read your email from wam.umd.edu
• VT-100 protocol allows only text
– The pine email program is designed for VT-100
• X Windows extension adds graphics
– X-terminals are available in CSS 4352
Electronic Mail (email)
• Person-person, one-one, asynchronous
– Mailing lists provide a many-many variant
• 690 mailing list is [email protected]
• telnet wam.umd.edu, login, and type “pine”
– Eurora & Outlook have similar capabilities
• But they store messages on the computer you are using
• The most widely deployed application
– Can reach intermittently connected users
– Often crosses firewalls
Email Addresses
• userid@machine (e.g., [email protected])
– Machine names are like postal addresses
• Most general part is at the end (.edu, .com, …)
• Most specific part is at the beginning (glue, …)
• Search engines use names to find addresses
– http://www.whowhere.lycos.com
• Finger uses an address to find a name
– On WAM, finger [email protected]
• Your userid (login name) is widely known
– Protect your password
Newsgroups (Usenet)
• Person-person, many-many, asynchronous
• Web browsers and pine can read news
– http://deja.com “discussions” are newsgroup archives
• Each “article” is stored once at each site
– Mailing lists produce one copy per person
– No need to “sign up” for newsgroups in advance
• Hierarchical organization
– Most general appears first (comp., soc., rec., …)
– Most specific appears last (rec.aviation.military)
Mailing Lists vs. Newsgroups
University of A
University of B
B1
A1
A2
Mail
Server
Mail
Server
B2
A3
B3
A1
B1
A2
A3
News
Server
News
Server
B2
B3
Talk
• Person-person, one-one, synchronous
• Design varies from system to system
– Talk command works with any unix machine
• e.g., talk [email protected]
• Must specify an exact machine name
– Instant Messages do the same thing on AOL
– ICQ and Microsoft Chat provide similar services
• Usually implemented with a split screen
– Both people can type at the same time
Chat
• Person-person, many-many, synchronous
• Like talk, but with lots of people
– Chat rooms on AOL, Internet Relay Chat (IRC)
• Whole lines are sent at a time
– Each line is labeled with the sender’s nickname
• IRC is not allowed on open lab machines
– Simply too popular!
Summary of the Seven Uses
Web
FTP
Telnet
Email
News
Talk
IRC
comp-comp
comp-comp
comp-comp
pers-pers
pers-pers
pers-pers
pers-pers
one-way
two-way
two-way
one-one
many-many
one-one
many-many
unauthenticated
authenticated
authenticated
sync
async
sync
sync
Computing at Maryland
• Computer Labs (PC, Mac, Unix)
– CLIS Library (2101 open, 2105 CLIS students only)
– PG2, EGR, SOM, WOR, CEN: Open 24 hours
– Need a “pay for print” account
• Dial-in access (Unix only)
– College Park (301)209-0700 (3hr)/864-2087(15min)
– Baltimore
(410)962-88865(3hr)/962-8867(15min)
– From other parts of the state, connect using Sailor
• Telnet access (Unix only)
– telnet wam.umd.edu from an Internet service provider
Homework
• Preliminaries (ungraded)
– WAM account, print account, email forwarding
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Email and mailing lists
World-Wide Web
Usenet Newsgroups
FTP
Questionnaire (ungraded)
Some Good Things to Do
• Take a peer training course
• Ask questions about readings
• Start thinking about your project
• Give us feedback