Spam Control Considered Harmful

John A. Tamplin jat at
Thu Oct 30 00:14:38 UTC 1997

On Wed, 29 Oct 1997, Dalvenjah FoxFire wrote:

> Is there a good reason why the throwway folks (those mentioned above)
> haven't blocked port 25 from their dialups to the outside internet?

We are an ISP and we don't block our dialups from going to port 25 elsewhere
because this would eliminate their ability to rightfully use another mail
server.  This frequently occurs when a user accesses a mail server at work
from their home dialup account.  If other ISPs did this, we would have a
problem where a user dialing into their ISP couldn't reach their virtual
mail server, hosted on our network.  We currently don't have many going
the other way, but that may change.
> The only reason I can think of that would stop this would be if a
> user subscribes to earthlink, but uses a UUnet dialin, that customer's
> software would be set up to use the Earthlink SMTP servers.

In our case, this doesn't help since we and all the other local ISPs block
relay access, so you have to use the mail server of the ISP you are
currently connected to.
John Tamplin					Traveller Information Services
jat at Traveller.COM				2104 West Ferry Way
205/883-4233x7007				Huntsville, AL 35801

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