Many protocols we describe below do one or both of these. However,
ordinary POP and IMAP do neither of these. This is a dangerous
problem. If you read mail with POP or IMAP, unscrupulous people on the
net can snoop on both your email password and the contents of your
message. This is not theoretical paranoia -- we see it happen all the
time. That's why we recommend secure mail Protocols.
Security is also important when sending mail. It is convenient for uses
with operating systems that do not have built in mail transport services
(e.g. MS Windows) to use remote SMTP servers. JTAN maintains SMTP
servers for this purpose, but it is important that these servers are
only used by JTAN customers. If they were left unguarded, spammers and
other evil doers would choke them with spam and other abusive stuff. For
everyone's benefit, outgoing mail servers must be secured against
unauthorized use.
Finally, a very important point that should be made with regard to many
of these protocols that encrypt your mail, like POPS and SMTPS. The
encryption used only protects your mail as it travels the first hop
between your mail client (e.g. Outlook) and our mail server. Although
protecting that first hop may be useful, as in the case of a wireless
link or if PLAIN SMTP/Auth is used, still you should keep in mind that
the mail server, there is no encryption. The only way to get full
protection for your mail from your computer to your recipient's computer
is to encrypt the message body itself. This must be done with a tool
like PGP/GnuPG or with the S/MIME
feature built into many mailers.
The workaround is to create a special mailer that you specify to
be used for the smarthost.
Edit your /etc/mail/sendmail.cf and search for the string "Msmtp". You
should find something that looks like:
Msmtp, P=[IPC], F=mDFMuX, S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=TCP $h
Copy and paste those three lines and modify the pasted lines so the
whole thing looks like:
Msmtp, P=[IPC], F=mDFMuX, S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=TCP $h
Msubmission, P=[IPC], F=mDFMuX, S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP, E=\r\n, L=990,
T=DNS/RFC822/SMTP,
A=TCP $h 587
Save the file, then edit the /etc/mail/mailertable file and add the line:
domain.com submission:[domain.com]
where domain.com is the smarthost. Next, restart sendmail by typing
"service sendmail restart" on RedHat or /etc/init.d/sendmail restart on
SuSE or Gentoo.
Now when you send to domain.com it will connect to port 587.