Andrei Popescu:
> On Mon, Dec 11, 2006 at 08:28:16AM +0100, Jochen Schulz wrote:
> >
> > On Debian, all ports are "open" by default (but there are not many
> > services listening, so it doesn't matter). If a service is being
> > installed, it can be assumed that it should actually be available. FTP
> > uses ports 20 and 21 (tcp), so if Ubuntu has some iptables rules
> > effective by default, you should make exceptions for these ports.
>
> Actually they are called "closed" if no service is listening
Yes, I know that, but thanks for the clarification anyway. That's why I
enclosed "open" in quotes, but I agree it was misleading.
> and "open" when some service (daemon) is listening. The ports
> protected by a firewall are sometimes called "filtered" (by nmap) or
> "stealth" (by some Windows firewalls).
But only when incoming packets are simply dropped (instead of properly
rejected, in which case the port is indistinguishable from ports at
which no process is listening).
J.
--
Nothing is as I planned it.
[Agree] [Disagree]
<http://www.slowlydownward.com/NODATA/data_enter2.html>
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