any hints are welcome to make my new system better.

You might want to use things like these http://www.saintcorporation.com/saint/ Network security scanner http://www.nessus.org/ Network security scanner www.lids.org Local ID www.snort.org Network ID www.rsbac.org rule based acl www.stunnel.org https tunnel 4 unprotected protocols or, as a long list try these Top 75 Network Security Tools www.insecure.org/tools.html Hope that helps Michael PS: One of my special "bastard operator" friends is: www.dansguardian.org