Re: SMTP behind NAT

Since this is a dorm, my guess is the university is simply trying to give themselves a fighting chance against any spambots or virus infections that install spambots on student computers (systems they won't be able to control). If 10 students run spambots that pump out of the same block of public IPs, they could quickly get blacklisted and that just plain sucks to deal with. Let alone the bandwidth that can consume for spam.

If you block outbound SMTP from everything but your own open relay that students can use, you probably block most of the spam that may be generated because it won't be smart enough to know there's an open relay nearby.

Likewise, if some student or attack is smart enough to see the open relay, your local admins will be able to track it a bit easier. Look at th open relay logs, find the computer spewing the garbage.

I would be willing to bet your university doesn't much care if you want to VPN to a mail server of your choice and send mail, or use a different port to connect out. I think they're just protecting their external IP profile and bandwidth.


<- snip ->
Is there a 'free' ;-) wireless connection involved here?
No. It's the network of a students dorm.

Regards,
Georg

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