Re: IP filtering

From: Karl Levinson [x y] mvp (jamescagney90210@excite.com)
Date: 01/30/03 

From: "Karl Levinson [x y] mvp" <jamescagney90210@excite.com>
Date: Thu, 30 Jan 2003 17:08:23 -0500

IP filtering won't prevent the server from listening. It might prevent the
server from responding. I"m also not sure the IP filtering feature will
block outbound connections, so that worms and other remote access trojans
might still be able to remotely control your computer or email out password
files or other data. There's also no logging or alerting or intrusion
detection, so if you're hacked, good luck finding the hacker.

Having said all that, closing a port is not just about filtering, it's also
about finding the service that's listening on a port and disabling that
service. Vision from www.foundstone.com/knowledge or www.google.com both
might help you determine what service to disable, as would posting the port
numbers here.

See here for some other things you might want to do to make sure your
computer is secure:

http://securityadmin.info/faq.htm#harden
http://securityadmin.info/faq.htm#closeport

"Sigitas Skublickas" <sskublickas@acf.hhs.gov> wrote in message
news:OgVzdHKyCHA.2684@TK2MSFTNGP11...
> Can anybody help me with this:
> I set up IP filtering on my NIC enabling only 20, 21, 80 and 3389 ports.
> How can make sure my server acceps calls ONLY on those ports? When
> I type in CMD netstat -a I get a list of at least 30 TCP or UDP ports
> that are in listening mode. Thanks in advance ! 

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