Re: Initial Installation Step 2

[Don Armstrong]

On Thu, 25 Jun 2009, Andrew Daviel wrote:
> On Thu, 25 Jun 2009, Don Armstrong wrote:
>> That's why you should generally just discard them instead of
>> rejecting. If you're fairly certain that it's spam, rejecting just
>> means that you increase the likelihood that people get backscatter
>> from forwarding MTAs.[1]
>
> I would rather let someone know that their mail has been rejected,
> than dedicate gigabytes of storage to spam on the offchance that
> some is legit, or tell someone that their flight confirmation or
> visa application might have gone to /dev/null.

Those are examples of automated messages, so no one will bother to
resend those; a reject is equivalent to /dev/null'ing it.

> I do get occasional queries from users about "I never sent that",
> but the volume of such is infinitesimal compared to the volome of
> spam, so I conclude it is not a significant problem.

I get about a 100 backscatter messages a day. It certainly is much
smaller than the amount of spam I deal with, but backscatter messages
have to be dealt with specially[1], because you want to see some of
them.

>> 1: From zombie machines in the networks of ISPs, for example.
>
> How common is that?

Fairly common, unfortunatly.


Don Armstrong

1: It's even worse that a large number of DSNs don't follow standard
paradigms, like matching procmail's FROM_DAEMON or similar.
-- 
No matter how many instances of white swans we may have observed, this
does not justify the conclusion that all swans are white.
 -- Sir Karl Popper _Logic of Scientific Discovery_

http://www.donarmstrong.com              http://rzlab.ucr.edu