[unisog] Port 25 blocking - on the

Paul Russell prussell at nd.edu
Fri Apr 29 19:39:17 GMT 2005

On 4/29/2005 10:44 AM, Paul Ryan wrote:
> Hi - I am doing a study on blocking port 25 outbound on our cable modems
> with the exceptions of approved mail servers. What techniques are used by
> the colleges/universities to workaround this - port 587,465,webmail etc ?

We block outbound port 25 connection requests from all but a short list of
known mail servers. Our central mail servers support authenticated SMTP
via TLS on ports 25 and 587, authenticated SMTP via SSL on port 465, webmail
via HTTPS on port 443. Our users also have the option of establishing a VPN
connection to our network.

Paul Russell
Senior Systems Administrator
OIT Messaging Services Team
University of Notre Dame

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