UC Irvine, Information and Computer Science Department Winter 2000

ICS 54: Brief Notes on Chapter 11: Electronic Mail


References

http://freesoft.org/CIE/Topics/91.htm
Section on Mail from Connected: An Internet Encyclopedia, http://freesoft.org/CIE
http://www.whatis.com/emaillis.htm
A tour of e-mail from http://www.whatis.com/, one of the best general purpose reference sites.
http://www.emailman.com/
Some good sections, but not all parts are well populated.
http://www.sendmail.org/
Sendmail Page
http://www.imap.org/
The IMAP Connection
http://www.garlic.com/~lynn/rfcietff.htm
Lynn Wheeler's IETF RFC Index


Electronic Mail Systems

Principal Functions of an E-Mail System

Principal Components of an E-Mail System

Examples:

User Agents (UA)

(Message) Transport Agent (= MTA)

Delivery Agent


Protocols and Standards

Protocol =

IETF = Internet Engineering Task Force, http://www.ietf.org/

RFC = "Request For Comment" (http://www.rfc-editor.org/)
Not all RFCs are standards, but some are and they are the standards on which the Internet is built (ftp://ftp.isi.edu/in-notes/rfc2500.txt)

SMTP = Simple Mail Transport Protocol

Example

% telnet gremlin.ics.uci.edu 25
Trying 128.195.1.70...
Connected to gremlin.ics.uci.edu.
Escape character is '^]'.
220 gremlin.ics.uci.edu Server SMTP (Complaints/bugs to:
Postmaster@ics.uci.edu)
EXPN ics54
250 ICS 54 Account <ics54@gremlin.ics.uci.edu>
QUIT
221 gremlin.ics.uci.edu says goodbye to igor.ics.uci.edu at Mon Feb 14 19:18:16.
Connection closed by foreign host.
%


POP3: Post Office Protocol -- Version 3


See RFC 1939


IMAP: Internet Message Access Protocol

See RFC 2060 and http://www.imap.org/


Encodings

Mail was meant to carry only "text." Binary information must be "encoded."

uuencode [ source-file ] filename
Encode source-file (or standard input) with the result going to standard output including filename at the start.
uudecode [ encoded-file ]
Decode encoded-file (or standard input) with the result going as specified by the filename included at its start.
mimencode [ -u ] [ source-file ] [ -o outputfile ]
Using "base64" encoding, encode (or decode if the -u option is set) source-file (or standard input) to produce outputfile (or standard out).
Note: If you want to try this, do so on the EA systems, rather than ICS systems.

Examples:

% cat message
Here is a message
for you.
% 
% uuencode message MyMessage > 2go
% 
% cat 2go
begin 600 MyMessage
;2&5R92!I<R!A(&UE<W-A9V4*9F]R('EO=2X*
 
end
% 
% uudecode 2go
% 
% cat MyMessage
Here is a message
for you.
% 
% cat message | uuencode Amessage | uudecode
% cat Amessage
Here is a message
for you.
% 


Multimedia Mail

MIME = Multi-Purpose Internet Mail Extensions
   Label content type and subtype

See "MEDIA TYPES" section of RFC 1700 for details or
MIME section of Connected: An Internet Encyclopedia for an overview.


Comments are welcome.
Current as of 14 February 2000
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