Re: [sa-list] Re: rule idea for catching 'zombie spam relays' and question of my logic

["Dan Mahoney, System Admin" <da...@prime.gushi.org>]

On Mon, 20 Sep 2004, Sherwood Botsford wrote:

In this case, you should get a "smart host" on some other mail server, and 
authenticate against that.  You are still an endpoint, and should not be 
directly talking to mail servers.  Only mail servers should talk to mail 
servers.

-Dan


>
>>> In my logic, there is no valid reason that a remote
>>> sender would connect directly to our SMTP server from
>>> their dynamic/DSL/cable IP to send our customer's an
>>> email ... I think ?  Valid 'remote to local' emails
>>> being sent from these DSL/cable/dialup IP would
>>> normally be relayed via their own network's SMTP
>>> server, which would then be delved to us by a host that
>>> didn't match the dynamic/DSL/cable custom rule. Right?
>>>
>>> It would either be a 'zombie' spam relay', or some one
>>> who setup a SMTP server on a dynamic IP (which just
>>> isn't what valid businesses do ... )?
>
>
> The school I work at is some 20 km from the nearest phone
> exchange.  DSL, ADSL, Cable are all non-starters here.  We
> connect through DirecPC oneway.  So our outbound connection
> is thorugh Telus, our local phone company.  They refuse to
> give out a static IP.
>
> Ok, so run your smtp through their server:  Fine, except
> they lose messages, or refuse to deliver them. (Remember
> one end is a satellite link, so the outbound packets have
> our direcpc address as the 'from' IP.  Their server thinks
> we're asking them to relay.)
>
> So I use smtp directly to most destinations.  The ones that
> won't accept our call because we have a dynamic address get
> sent to Telus, where eventually they get handled.  (Why
> some get bounced, and others not still escapes me.)
>
> This is an example of one business/institution that relies
> on a dynamic IP.
>
> --
> Sherwood Botsford
> St. John's School of Alberta
>

--

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--------Dan Mahoney--------
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