Transcript Internet

Introduction to Networks
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Most people work in a network
environment
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Home network
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Local Area Network (LAN)
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Wide Area Network (WAN)
The physical structure includes:
interface cards, cables, hubs,
switches, and routers
Protect your password!
From LAN to WAN
(a) Home Network
(b) Local Area Network
From LAN to WAN
(continued)
(c) Wide Area Network
The Internet and World Wide Web
and Email
Welcome to Cyberspace
By
Robert T. Grauer
Maryann Barber
Modified by Lin
Objectives
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Define the Internet and give a brief overview of its history
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Briefly introduction TCP/IP
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Describe various buttons on the Internet Explorer toolbar
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Explain how to save the address of a favorite Web site
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Describe how to safeguard a system through acquisition of an anti-virus program
and through systematic backup
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Distinguish between the Boolean operations And, Or, and Not
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Describe the structure of a Web address
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Download a graphic from the Web
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Draw several parallels between e-commerce and traditional commerce
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Distinguish between the http and https protocol; define a cookie and explain how
it is a potential threat to individual privacy
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Create a Web Page (HTML document) using Microsoft Word
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Describe Email
The Internet
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A network of networks
Began in 1969 as ARPAnet
(Advanced Research Projects
Agency)
No central authority and thus
impossible to state the precise size
Internet Applications (1)
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E-mail: is a means of communication on the
Internet, and one of the first applications on it.
Telnet: or remote login, allows your computer to
login to a remote computer and act as though it
were a local terminal attached to that computer.
Ftp allows you to transfer files from or to a remote
computer. It is commonly used to download
software. ftp sites can be accessed with URL
starting with ftp (e.g. ftp://…
Internet Applications(2)
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Newsgroups: use Usenet to share discussions on a
specific topic. Ex: rec.arts.books is a group for the
discussion of books and book reviews.
WWW: provides access to a rich universe of
information and computer data, and is the basis for
much of today's Internet activity
How Internet Works (TCP/IP)
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Transmission and control protocol
Internet Protocol
How TCP/IP works: IP is able to find
a path, TCP breaks data into
packets, send each packet from one
end (with an IP address) to the
other end (with another IP address)
in some route, and assemble them
at the other end
WWW
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An Internet application
The World Wide Web
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A subset of the Internet consisting of all
computers with hypertext or hypermedia
documents
These documents contain references
(links) to other documents which may be
on a different computer anywhere in the
world
Began in 1991 at the European Particle
Physics Laboratory (CERN) in Switzerland
Acronyms Abound
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HTTP – HyperText Transfer Protocol
is used to transmit Web documents
HTTPS – Secure protocol for
confidential transactions
HTML – HyperText Markup
Language is the language for all
Web Documents
ISP – Internet Service provider
Connecting to the Internet
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At Work or School
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Via a Local Area
Network
At Home
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Traditional Modem
(56KB)
Cable Modem
DSL Modem
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My Connection
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Via the university’s
network connection
in the dorm
Via Ethercard
connected to the
Data Jack via
network cable
Microsoft Internet Explorer
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Menu Bar
 File
 Edit
 View
 Favorites
 Tools
 Help
Address Bar
 URL
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Toolbar
 Back Button
 Forward Button
 Stop
 Refresh
 Home
 Search
 Favorites
 History
Tool Bar
Address Bar
Hyperlinks
Status Bar
Uniform Resource Locator (URL)
http://www.annex.com/southwest/museum.htm
Document
Path (Directory or Folder)
Internet Address (Web site)
Means of access,
HyperText Transfer Protocol
Examples of URLs
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Microsoft: www.microsoft.com
University: www.miami.edu
Grauer Site: www.prenhall.com/grauer
General reference: www.refdesk.com
Anti-virus updates: www.symantec.com
Download software: www.tucows.com
You can guess at the URL using the
general form: www.company.com
Hyperlinks
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Provide text, graphics, sound, or video links
Blue underlined fonts are unexplored
www.unexplored.link
Magenta links have been previously accessed
www.explored.link
Returning to a Previous Site
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Back Button
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Favorites List
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Returns to
pages in this
session
Returns to
selected
pages
History List
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Returns to
pages from
previous
sessions
Search Engines
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A program that systematically searches the
Web for documents on a specific topic
Uses a key word or words as a query
Several search engines are available
Each search engine has its own database
No search engine is best
Uses Boolean (logical) operators
Returns “hits” or documents once search has
been submitted
Click the Search Button
• Relevant sites
(hits) are
shown in left
pane; selected
page is in the
right pane
• Repeat the
search with
multiple
engines for
other pages
Popular Web Search Engines
http://www.altavista.com/
http://www.msn.com/
http://www.go.com/
http://www.excite.com/
http://www.lycos.com
http://www.askjeeves.com/
http://www.webcrawler.com/
http://www.google.com/
http://www.yahoo.com
http://www.search.com/
Suggestions for Searching
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Use the Search button on the Internet
Explorer Toolbar
Try multiple search engines on one query
Be aware of logical operators - AND, OR,
and NOT
Search on a concept: e.g., “first ladies”
rather than “Eleanor Roosevelt”
Set Bookmarks/Favorites
E-commerce
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The exchange of goods and services
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Buyer and seller
Products and suppliers
A place to “meet”
Marketing to attract the buyer
Accept and process the order
All of these elements are present in
e-commerce and traditional
commerce
Advantages of E-commerce
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For the Seller
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Open 24/7
Shoppers from
anywhere
Virtual inventory is
cheaper and
extensive
Lower transaction
costs
Target your
customers
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For the Buyer
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Open 24/7
Never leave home
Easy to view and
explore product
line
Comparison shop
Web site knows
you
Security and Privacy
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Secure transactions
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Https protocol
Encryption
Privacy
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Cookie is a small file written to your
disk each time you visit a site
Problem is when one site can read
many cookies, e.g., Double Click.com
Creating a Web Page
• Use Word to
create the
document
• Use the
Save As Web
Page
command to
convert to
HTML
• Upload to a
Web server
Email
Electronic Mail (E-mail)
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E-mail is sending messages via
computer
Business is using more e-mail and fax
To access you must have a mail server
and software
Each person has a username and
password
All mail programs allow you to Send,
Compose, Reply and Forward, Delete
E-mail Protocols
POP Client --Post Office Protocol
•Mail is read composed and stored locally
•Can work off-line
IMAP --Messages stored remotely
•Stored on a server
•Download for local storage
SMTP --Simple Mail Transfer Protocol
•The protocol required to send mail messages
through the Internet
Email
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To connect to your Mailbox:
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Double-click the Outlook Web EMAIL icon
This opens to the StFX Web Mail page in IE
Mailbox Window:Toolbar, Outlook bar,
Navigation toolbar, and messages in bottom
# read and # unread messages
Send a Message
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To send an email, you need to know
the mail address, ex: [email protected];
Click on New message button
Look at
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To: the address of the recipient
CC: send copies to others
Subject: message contents
Type the subject and contents, click
Send.
Reply to a Message
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Click on message header you want
to reply to, click Reply button –
Reply to sender
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can also Reply to All
Go to message section and add
your text wherever you want
Click on Send button
Forward a message
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Click on the message header you want
to forward
Click on Forward button
Put in the To: the mail address you
want to forward to, you can change
subject box
You can add a message to the
message section;
Click Send button.
Attaching files to your mail
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Begin composing a new letter
Click on Attachments link, or
Attachments button on the
toolbar.
Your attachment is usually a file
that you either know the path name
for or you can browse for it.
Fill in other sections as usual and
click Send.
Reading messages with
attached files
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Click on attachment in message
window
Message is directly readable with
the same systems on sending and
receiving end
When receiving on some systems,
attachments may have to be saved
first and read later with the correct
software application.
Mail Folders
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You can organize your messages in
folders
Click on Folders button in the
Outlook bar and show the various
folders you have available
Some predefined folders: Trash,
sent, personal, drafts, inbox
Create folders
Move messages to a certain folder
Filing Messages to a Folder
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To create a mail folder in your mailbox,
right-click on the parent directory and
choose Create New. A text box opens
for you to name the new folder which will
be a sub folder.
File messages to the selected folder.
The message is deleted from the inbox
and now appears in the folder you have
chosen.
Removing Messages
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Sending unwanted messages to the
Trash folder
Click on header and then click on Delete
button
If more than one letter is to be deleted,
hold down the CTRL key and then click
succeeding headers to select them
Contacts
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Adding names to your Contact list
Click on the Contact button on the toolbar
or the Contact icon in the Outlook bar, Fill
in all the information.
Using the address book
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While addressing a message: click the Contact
button and select the person, click on To: or CC:,
click on OK
If you simply want to send the message to
multiple persons, simply click on the line below
the previous address and either type the address
or insert it from address book after the TO:
appears.
Instant Address – copying the address from a
message directly into your address book
Summary
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The Internet is a network of networks
Internet Explorer/Netscape Navigator are browsers
URL is located in the Address Bar
Connect through ISP or LAN
Search Engines are the tools to find information
Learn to use keywords for searching
Use multiple search engines
Searches are based on Boolean operators
Web documents are written in HTML
The Save As Web Page command converts a Word
document to HTML
Emails and contacts