Understanding
E-Mail |
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| email address |
E-Mail Addresses: UserID@[hostname.][subdomain.]domain
webmail - http://webmail.edinboro.edu
sign-on using username and password
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| Email Client |
E-mail client (MS Outlook, Eudora...)
- Displays a list of received messages
- Provides options to select and read messages
- Provides options to create and send messages
- Provides way to add attachments
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| email server |
E-mail server
- Runs all the time listening for a specific port (25)
- Maintains a list of all e-mail accounts
- Appends new messages onto end of e-mail account file
two parts:
SMTP - Simple Mail
Transfer Protocol (listens for port 25)
does most of the work
POP3 - Post Office
Protocol (listens for port 110)
maintains the text file and communicates
with e-mail client
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Communicate with
email server |
| Try This: Communicate with the email server
on cslab103:
Windows from the command prompt
or Linux from the dollar
prompt -
telnet
cslab103.cs.edinboro.edu 25
(connects to SMTP)
helo test
mail
from:test@aol.com
rcpt
to:yourusername@edinboro.edu
data
this is a test of
email
.
(period on a line ends data
& sends msg)
quit
--> check webmail screen & read test message
look at the headers of the email
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|
email
attachments |
E-Mail Attachments
- file contents appended on the end of the
message
- E-mail client determines how this will be processed
Try This:
- Create a small file in notepad ("this is my attachment")
- Create a small image file (save an image from the web
locally)
- Use webmail and send yourself two messages
- one with the notepad file attached
- one with the image attached
- Telnet to VMS and sign-on
- Run the VMS mail client and list the new mail
- Read the mail and notice the attachments
- the notepad attachment is readable
- the image attachment is not readable
- Read the mail in webmail and notice the attachments
- both are readable/viewable
Not ALL email clients handle attachments!
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| More on email |
How
Email Works
|