Cybersecurity

I agree with Neo.

More, I am not spammer. This question is coming from the privacy concerns.

More secure email protocols other than SMTP should be invented. Don't you think so?

Yes, now that the use of email has matured, a more robust and secure email protocol would be appropriate. However, it is both human nature and the nature of the IETF to 'pave over cowpaths' so there is little chance that SMTP will be redesigned (and actually used) in the next decade. The trends in IT are to modify and tweak broken legacy systems.

So, we are 'stuck with SMTP' for the forseeable future. However, mail can be sent using SMTP quite securely using PGP and other encryption methods. Originating IP addresses can be hidden; or anonymous remailers can be used (or both!!).

A little broad, I admit....just trying to make the point that obscuring the IP address in your email would probably not make one bit of difference to deter port-scans, etc.


I still maintain that it is extremely bad netiquette to intentionally spoof your email headers. Use anonymous remailers instead. If you have ever tried to diagnose a mail system problem, then you should realize the importance of accurate headers... they are put there for a reason! Don't bend the rules of the protocol because they don't suit your tastes. (This is something that Microsoft likes to do...)

Calm down, man. I don't really intend to hide IP in my mail headers. But we ought to know how to do this, right?

OK, let's come back to the original question. I checked the file /etc/sendmail.cf and I found it contained definitions of mail header format. Like following,

�@�@H?P?Return-Path: <$g>
�@�@HReceived: $?sfrom $s $.$?_($?s$|from $.$_)
�@�@H?D?Resent-Date: $a
�@�@H?D?Date: $a
�@�@H?F?Resent-From: $?x$x <$g>$|$g$.
�@�@H?F?From: $?x$x <$g>$|$g$.
�@�@H?x?Full-Name: $x
�@�@H?M?Resent-Message-Id: <$t.$i@$j>
�@�@H?M?Message-Id: $t.$i@$j

I don't think it is easy to understand. Any specialist ever tackled this file? BTW, voodoo, seems something from Africa... Working with voodoo.c may be too difficult for me.

Thanks for your interests!

Eddie

Yes, you can monkey with sendmail.cf and have lots of fun. However, there are a lot more header information than the ones you posted, so you have to dig deeper into the headers and how the headers are generated. The sendmail book by OReilly is good for this.


As far a the intent of the SMTP protocol, I don't think there is a documented book on the thoughts of the late Jon Postel why he created the protocol as he did. I don't think that when SMTP was invented, Jon or anyone in their wildest dreams, conceived of how email is vastly used today. Spam, privacy, security, all of the topics were not even in the back-of-the-mind when SMTP the IETF RFC was created. Back then, folks were just trying to send messages between diverse organizations and even the use of the @ system was NOT standard.

So, I think it is a leap of the imagination to discuss what was in the mind of Jon Postel and SMTP mail in 1980s; with the exception of trying to get clumsy and clunky email to work with IMP processors created by BBN

Suggest folks interested read "Where Wizards Stay Up Late" where this is discussed (the origins of the Internet); and the first (or one of the first) email messages, sent my Professor Kleinrock, to seek his lost razor after a trip.


This book is a must read for all interested in the real origins of the Internet (and not the modern hype).

Good suggestion.

Let us think why we do not have so severe spam problems in the real mail system (paper mails, not email). Because of postage. Email spammers send emails without paying postage.

I am thinking if we can imagine that emails should be added with electronic postages prior to being submited to the Email server. I think, with so developed computer technology we have, it is not a dream. Although this comport may incur widespread objections, I still believe E-postage could be a prospect of our future email system.
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Interesting suggestion, e-postage for e-mail. You strike me as someone who 'thinks out of the box' and sees life as a set of infinite possibilities vis-a-vis constrained by the mistakes of the past.

As far as email spam, I receive much more e-mail spam than postal spam and junk mail; but I am much more troubled by junk mail in my postal mail box. Here is why, just Neo-think:

Postal junk mail (junk mail) is bulky, contributes to deforestation (paper based) and global warming, and worst of all (selfish me) sometimes hides the good mail (I've lost important bills tossing out the junk). So, you must 'sort and seek' the pile of junk mail and are forced to handle.

E-mail junk, on the other hand, is more easily managed. I know the domains and people and subjects I find critical, so I filter these into special folders. Default junk (spam) goes to a generic in box. Not withstanding spam and junk filters and blockers, I can easily delete spam with the delete key. So, even when I'm heavily spammed, the time-to-delete is trivial.

Granted, in a rush to delete spam, I've deleted a few good messages, but this is unusual.

So, as much as I have a distaste for spam, I do not find it 'more evil' than things like:

- standing in line
- getting junk mail in my US mail box
- deleting and moving posts in the UNIX forums
- cleaning the house
- fileing papers
- you get the idea

So, it is quite popular to 'call email spam the evil-of-the-world' but, quite frankly, I can name 100s of events than make spam trivial, relatively speaking.

Not that I like spam, but you can make your spam life easier by using temporary mailing addresses and doing things like:

-register with web-sites as neo_web@domain.com or mail@yourdomain.com and by doing these tricks, minimize spam in your inbox.

-do not put your email address in newsgroups and other public forums that are archived and mined

-be careful about your main and favorite email addresses with other public documents.

I'm running out of brain-fodder

Neo