Thanks, yes, let us stay on the technical side of this question since there is no correct answer for the social side.

AIM actually can detect open port and switch to that port. Once I opened only outgoing port 80 and 53(DNS), and I found later AIM was using 53.

I think the filtering needs to be on layer 7, maybe something like snort.

In reply to Re: A perl personal firewall? by johnnywang
in thread A perl personal firewall? by johnnywang

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