Column headers for the "Current connections" windows would be nice, for those who didn't write the app.

Line 68: make that a parameter, or check for /etc/resolv.conf and get the value from there.

Line 134: right.

There's a classic blunder at line 143: check to see if the regexp actually matched before you use $4 elsewhere.

At 157, you should check to see if $connlist[$i]{rip} is defined before using it as a hash element. Also, the () around an unless or if modifier aren't necessary.

Line 218, assign a default value to $portnum to avoid another undefined value error.

And so on. Some basic cleanup before posting is a nice thing, but it's a good start.