Re: Decentralized reliable instant messaging?
On Tue 30 Aug 2016 at 15:05:02 -0400, Henning Follmann wrote:
> On Tue, Aug 30, 2016 at 05:49:34PM +0100, Joe wrote:
> > On Tue, 30 Aug 2016 09:59:42 -0400
> > Henning Follmann <hfollmann@itcfollmann.com> wrote:
> >
> > > On Tue, Aug 30, 2016 at 02:52:14PM +0100, Lisi Reisz wrote:
> > > > On Tuesday 30 August 2016 14:05:36 Stefan Monnier wrote:
> > > > > "shocked that anyone would want to design or use an
> > > > > unreliable messaging system"
> > > >
> > > > Email is getting less and less reliable, so have you given up using
> > > > it?? :-(
> > > >
> > > > Lisi
> > > >
> > >
> > > However, why email is still reliable, because a proper setup provides
> > > you with a well defined error messages (in case it is not delivered).
> > >
> >
> > If an email is designated as spam, it will be *silently* dropped. It
> > took mail admins a long time to realise that if a message was spam, the
> > last thing they should do with it is to 'return' it to the apparent
> > 'sender' as part of a bounce message.
> >
>
> You have a much too simplistic view of todays anti-spam measures.
>
> If an smtp server tries to deliver a messages, usually the first the
> receiving server does, during the helo, checking if the sending server is
> blacklisted. If blacklisted any attempt to deliver any mail will be denied
> and the sender will receive a proper 5XX error message.
brian@desktop:~$ telnet itcfollmann.com 25
Trying 96.242.112.3...
Connected to itcfollmann.com.
Escape character is '^]'.
220 newton.itcfollmann.com ESMTP Postfix (Debian/GNU)
helo spammershaven.com
250 newton.itcfollmann.com
mail from:yourneighbourhoodspammer@gmail.com
250 2.1.0 Ok
rcpt to:hfollmann@itcfollmann.com
450 4.2.0 <hfollmann@itcfollmann.com>: Recipient address rejected: Greylisted, see http://postgrey.schweikert.ch/help/itcfollmann.com.html
I don't really want to go to the data command or go through this
greylisting business but the helo command seems acceptable to your
server.
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