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Electronic mail
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E-mail: summary
The following gives an overview of electronic mail:
• What it is
• Using e-mail through the WWW
• Using e-mail with a dedicated e-mail client software
• …
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E-mail: prerequisites
Before using e-mail, you should ideally have some knowledge and skills related to
• computer hardware
• computer software
• the Internet
• the WWW
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E-mail: general description
Electronic mail allows network users to send messages to each other by computer. The process is like the postal system in some ways, but in the case of electronic mail, the mail agent is a computer program
»the address for sending is the address of an electronic mailbox
»the message is given to the mail system electronically, not on paper
»the transport system is the data communication network
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E-mail using central, isolated systems
E-mail computer
E-mail computer
1 A 2 B
SendSend ReadRead
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E-mail usingstore and forward systems
E-mail computer
I
E-mail computer
I
1 A 2 B
E-mail computer
II
E-mail computer
II
Send Read
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E-mail:examples of global systems
• Systems with 1 intermediate e-mail computer offering a central bulletin board + gateways to other systems
CompuServe (in US), Data-Star (in Switzerland), Dialog (in US), ESA-IRS (in Italy),...
• Global systems using more than 1 intermediate store and forward e-mail computer + gateways to other systems + decentralised bulletin boards
BITNET, Internet SMTP, X-400 network, UUCP network, FidoNet,...
Examples
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E-mail: getting started
To start, you need:
• a networked computer
• a mail system (software)
• a personal mailbox for you
• a little know-how
• e-mail addresses, if you want to send messages
• ...
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E-mail: benefits
• Overcomes time zone problems inherent to telephone
• Faster than classical mail
• International
• Inexpensive (free of charge in academic institutions)
• Data are kept in computer readable form
• Send to more than 1 address in 1 action
• Easy to include received message in the reply
• Allows discussion forums & “journals” based on e-mail
• ...
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E-mail addresses of persons (Internet style)
An electronic mail address is the string of characters that you must give an electronic mail program to direct a message to a particular person:
username@computer-address
Examples:
»(Bitnet: [email protected])
»Internet U.S.A.: [email protected]
»Internet not-U.S.A.: [email protected]
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!? Question !? Task !? Problem !?
What is your full personal Internet mail address?
What is your full personal Internet mail address?
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E-mail: reading and managing messages
• On-line =
Linked to the e-mail server computer even when reading and managing messages; for instance:
—using telnet to login to an e-mail computer
—using WWW to login to an e-mail computer
• Off-line ! =
On-line only to download messages from the server, and reading and managing messages, NOT linked to the server computer anymore !
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E-mail through the WWW: international systems
• Some international systems based on the WWW allow you to send and read/receive e-mail messages.
Examples: Hotmail of Microsoft, Webmail of Netscape = Net@ddress, Yahoo Mail
• Some international systems based on the WWW allow you to receive/read the messages from the POP mail account provided by your ISP.
Example: Yahoo Mail
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E-mail through the WWW: local systems
• In many institutes, local systems restricted to users of the institute, offer services related to e-mail based on the WWW.
»Example: at the universities in Brussels: http://www.ulb.ac.be/tools/webmail.html
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!? Question !? Task !? Problem !?
What are the advantages and disadvantages
of e-mail through the WWW, in comparison with other systems?
What are the advantages and disadvantages
of e-mail through the WWW, in comparison with other systems?
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E-mail through the WWW: advantages
• Available from any WWW browser, and thus suitable when traveling.
• Client software dedicated to e-mail on your microcomputer is not required.
• Your e-mail address on a public system may be more stable, may last longer, than an e-maill address provided to you by the institute where you study or work.
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E-mail through the WWW: disadvantages (Part 1)
• Uses the network inefficiently, when the sender and the receiver are close to each other, but far away from the e-mail computer.
• Disk space to receive and manage messages in the international systems free of charge is in most cases more limited than in other e-mail systems.
• Less reliable than good local e-mail systems.
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E-mail through the WWW: disadvantages (Part 2)
• Works slower in most cases than using directly an e-mail client on your microcomputer.
• Some systems do not allow
»filtering messages
»receiving file attachments
»sending file attachments
• (Not well integrated with e-mail “mailto:” hyperlinks.)
• (Advertisements can distract users.)
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E-mail: client programs for an Internet microcomputer
• From a microcomputer with a network card, you can use a client program which ‘sucks’ / ‘downloads’ the messages from the local area e-mail network server.
• Most of these programs are easier to use than character-based programs for Unix.
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E-mail + WWW client programs for an Internet PC with Windows
• Netscape
(combined with a good WWW browser and a simple Usenet client)
• Microsoft Internet Explorer, including a mail client Microsoft Outlook Express
(combined with a good WWW browser and a simple Usenet client)
• ...
Examples
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!? Question !? Task !? Problem !?
Which method for e-mail do you or will you use?
Which method for e-mail do you or will you use?
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!? Question !? Task !? Problem !?
Read your incoming mail.
Send a simple ASCII message(for instance to yourself).
Read your incoming mail.
Send a simple ASCII message(for instance to yourself).
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!? Question !? Task !? Problem !?
Can you send and receive other information types
than simple text and numbersby electronic mail?
Can you send and receive other information types
than simple text and numbersby electronic mail?
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E-mail more than ASCII text and numbers
Transmission of data other than ASCII texts is possible by
• encoding a non-ASCII file to ASCII,
• enclosing it in the message, and
• decoding the file to the original non-ASCII file at the receiving end.
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!? Question !? Task !? Problem !?
Which kind of files can be sent as attachments?
Which kind of files can be sent as attachments?
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!? Question !? Task !? Problem !?
Send a simple text e-mail message to yourself, receive it, and read it.
Send a non-text file to yourself, by e-mail, receive it, and view or execute it
(for instance a word processing file).
Send a simple text e-mail message to yourself, receive it, and read it.
Send a non-text file to yourself, by e-mail, receive it, and view or execute it
(for instance a word processing file).
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E-mail: future trends
• more users
• availability of global e-mail address directories
• from simple text to multimedia and hypermedia e-mail
• from simple ASCII text e-mail to voice e-mail, to Internet telephone, to network video-conferencing
