Re: Blocking port 25 outbound

[Michael Halm <Michael.Halm () CCMAIL NEVADA EDU>]

We don't exactly block port 25. We have a list of authorized mail servers.
If any other host sends on port 25, the traffic is forwarded to our box
and an e-mail is sent to the sender explaining the procedure to get their
mail server authorized. Our NOC is notified and we sniff to see if the
mail is spam. Then we track down and contact the owner of the box.

 

We made an initial effort to identify all our smtp servers before we went
live. Once we added the few we missed this system has made our lives a lot
easier. And we are better netizens as well.

 

Michael Halm

University of Nevada Las Vegas

4505 Maryland Parkway

Las Vegas Nv  89154

702-895-0726

 

-----Original Message-----
From: Lazor, Joseph [mailto:JLazor () ADMIN FSU EDU] 
Sent: Monday, August 22, 2005 12:30 PM
To: SECURITY () LISTSERV EDUCAUSE EDU
Subject: [SECURITY] Blocking port 25 outbound

 

Hello out there,

 

We are considering blocking all port 25 traffic outbound.  We have noted
various ISP's and others moving to block port 25 outbound to reduce
"spamming".  We wish to be good "netizens"

Have any of you done this already and what has been the push back of
issues related to implementation on your campus?

 

Regards,

 

Joseph A. Lazor

Florida Sate University