RE: SMTP behind NAT

["Murda Mcloud" <murdamcloud () bigpond com>]

Ahh, now I'm beginning to understand
> > I personally use a VPN connection to send my mail. I was just wondering
> > what
> > could be the point in enforcing these firewall rules.

Well, if it were my network then I would also want to control, filter and
monitor egress as well as ingress. But then I have become more paranoid in
my old age. Even at home I do that-I filter both ingoing and outgoing.
One reason being that I want to make sure that if Trojans etc are active in
my network then I have a greater chance of noticing and taking appropriate
action. I guess at heart I'm a 'default deny' type of guy.

If I just had an 'allow-outgoing-any to any' type of rule then I couldn't
track any potential problems. Also, I wouldn't fancy letting an smtp server
be an open relay from behind a network either but that's because I can't see
a business case for it where I am. Perhaps there is a 'college/student' case
for it where you are(?) 

To be honest, I'm now wondering why they would block access to external smtp
servers if they allow their own one to be an open relay. Not really sure
what the overall stance is aiming for. If they're aiming for
convenience(like with the open relay) then why not allow you to access some
other servers on 25? I'd be interested in their answer if you ever get one.

Maybe they had some default rules and just never really modified them? Or
it's easy for them to do what they need and they don't care too much about
the students? All conjecture on my part.








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