New ZeroConf Spec

Dan Kegel dank at
Tue Jul 4 17:52:25 BST 2006

On 7/4/06, Scott James Remnant <scott at> wrote:
> > There should be no exception: there should be no open ports by default.
> >
> This isn't actually entirely true; we currently have two open ports by
> default:
> If you're on a network with DHCP, the DHCP client listens on UDP port 68
> to receive responses from the DHCP server.
> And every time you make a DNS query, a UDP port is opened to receive the
> response from the DNS server.

Both of these are examples of getting replies to queries sent out by the
system, so they don't count, really.
- Dan

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