Remote email access

Mike Tancsa mike at sentex.net
Fri Jan 31 02:03:23 UTC 2003


At 05:46 PM 1/30/2003 -0800, Dave Crocker wrote:

>Blocking outbound SMTP (port 25) is supported by the Ops community as a
>spam-suppression mechanism. Ops support for this blockage appears to be
>deeply and broadly held.

A large chunk of the spam I am seeing these days are due to exploitable 
formmail.pl scripts (i.e. insecure customer web apps) and open proxies 
(1080,8080 3128 etc).  These forms of delivery are also preferred by 
spammers as their original IP addresses are hidden.   Blocking port 25 will 
do nothing to stop this.

I would be surprised if your premise holds true, that the majority of the 
Ops community support this. Blocking port 25 results in lost customers as 
well as additional support headaches. I know when the local big ISP 
(Sympatico) starting blocking port 25, we gained quite a few business 
customers.  So our sales staff certainly supported their Ops implementing it.

         ---Mike
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Mike Tancsa,                          	          tel +1 519 651 3400
Sentex Communications,     			  mike at sentex.net
Providing Internet since 1994                    www.sentex.net
Cambridge, Ontario Canada			  www.sentex.net/mike




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