Re: wireless router off a normal router

In article <2voho1h9bu064mc7ou2c49nt5u5dd1o0kb@xxxxxxx>,
Phil Earnhardt <pae@xxxxxxx> wrote:

[...]

> >In article <p2kfo1df365sa0dq1d94ff6b0p93kmedfn@xxxxxxx>,
> > Phil Earnhardt <pae@xxxxxxx> wrote:
> >
> >> On Thu, 24 Nov 2005 05:57:39 -0800, nospam <nospam@xxxxxxxxxxxxxx>
> >> wrote:

[...]

> >> >turn OFF dhcp on the wireless router (you do not want more than one
> >> >dhcp server on the same lan).
> >
> >[...]
> >
> >> What I don't understand is why it is needed.

[...]

> The root of my question: what constitutes the "same subnet"? It would
> seem that a router running DHCP and NAT services has essentially
> created a distinct subnet.

I think the issue is obscured by the fact that many boxes are both NAT
routers and DHCP servers (and firewalls, etc.). But they're still 2
different things, even though they live in the same box.

The NAT router defines the range of the subnet. A DHCP server on that
subnet hands out IP leases to devices on that subnet.

So if you'd have a second DHCP server active on that same subnet, you'll
get problems. Whether that second DHCP server lives by itself, or shares
a box with a NAT server is irrelevant *unless* that NAT server is active
and creates its own subnet on the DHCP server is active on *that*.

> The person I'm working with said that he was told he "couldn't have
> routing" on his wireless;

The problem with such statements is that all by themselves they are too
absolute. I would assume the statement refers to a specific context -
wanting to set up a network with specific capabilities. For instance,
like someone else says: Bonjour (aka,Rendez-Vous aka Zero-Conf) doesn't
work across subnets. So if you'd want to use Bonjour across wired and
wireless machines, indeed you'll have to set up the Airport box as a
bridge.

Someone else may *want* to create a different subnet and therefore
*need* to enable routing on the Airport.

--
Sander Tekelenburg, <http://www.euronet.nl/~tekelenb/>

Mac user: "Macs only have 40 viruses, tops!"
PC user: "SEE! Not even the virus writers support Macs!"
.

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