Author: Bill Hayles Date: To: exim-users Subject: Re: [exim] Gmail's new 'suspicious sender' flag
Hi, Ian
On Wed, 6 Jul 2011 16:26:03 +0000 in message number <EF12875F-8AA3-4895-B7EE-6F3E02105A69@???>, received here on 06/07/2011 21:27:50, Ian Eiloart <iane@???> said:
>
> On 6 Jul 2011, at 15:36, Bill Hayles wrote: > > Which is why my server does NO spam filtering. It's up to the users what to
> > do about spam; for all I know they may be interested in those offers from
> > the kind people in the penis enlargement lobby. That's how my users like it.
> >
>
> The trouble with that is that the ideal situation is that spammers simply
> can't deliver their email. If you check at the MTA, then you can arrange
> this (false positives and false negatives notwithstanding).
This could lead to tears at bedtime, so I won't pursue it, but one reason
for my starting my own server was that I don't want any third party deciding
what mail I should or should not receive. That's entirely up to the end
user, just as the Post Office don't decide what is and isn't junk mail. My
users know (and prefer) that it is up to them to deal with spam. As a matter
of principal I pass through everything. >
> If you leave it to the end user, it's too late to reject the email.
Not necessarily. There are several end-user anti-spam packages, such as
Mailwasher, which will bounce rejected mail and make it appear that the mail
was never delivered. However, I think that's a dubious practice as most
spammers take no notice, it adds to the volume of useless traffic on the net,
and you could be bombarding somebody unfortunate enough to have an address
used by the spammers. Therefore I don't do it, and encourage others not to
either.
>As far as the spammer is concerned, the email is delivered.
Do they ever take any notice of bounces? Given the number of mails
continually sent to non-existent addresses (which obviously ARE rejected) I
don't think so. I know I only run a very small server, but the volume of
mail received by what I term "blunderbuss attacks" far exceeds spam to
genuine addresses. By blunderbuss what I mean is that the spammer obviously
has a list of common user names - john@???, peter@??? etc,
and sends mail in the hope that the address exists. With large mail servers,
they probably do. For a domain and server with 25 or so accounts, very
often they don't, but they still arrive despite the bounces.
