Is NAT can provide some kind of protection?

William Herrin bill at
Sat Jan 15 15:43:55 CST 2011

On Sat, Jan 15, 2011 at 4:16 PM, Brian Keefer <chort at> wrote:
> 1.)  Allows you to redirect a privileged port (on UNIX) to a
> non-privileged port. For daemons that don't implement some
> form of privilege revoking after binding to a low port (and/or aren't
> allowed to run as root), this is very useful.  It's much easier to
> have a firewall redirect than to implement robust privilege revoking.
>  Example: PAT 25/tcp -> 2525/tcp.

There was a patch offered for the Linux kernel years ago that exported
the network ports as a filesystem where you could set who could bind
which port by changing the ownership and permissions on the "files." I
never understood why Linus rejected it.

Bill Herrin

William D. Herrin ................ herrin at  bill at
3005 Crane Dr. ...................... Web: <>
Falls Church, VA 22042-3004

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