Re: Default Gateways.

[David Lapp <[e-mail]>]

> 
> Sorry for the overdue reply to this, but I've been on vacation and just now
> catching up...
> 
> Bret's idea touches on a fringe that may require further consideration.
> Using a  local host's address as its own default gateway seems to have a lot
> of popularity in dial-up (check out "ipconfig /all" or "winipconfig" on a
> Mickeysoft PC's PPP adapter).  It has also found use in avoiding renumbering
> hassles as default gateway addresses change.  I saw no responses to Bret's
> query beyond that attached.  Anyone else see a need?  Is Bret's issue a MS
> NT limitation (scuttle of late sez MS seems rather free-willed with
> implementations of some IP standards) or is this a simple case of DHCP v4
> never did it that way and never will?
>
This sounds like an implementation detail. I don't recall the DHCP
spec speaking to the issue of what addresses are valid as "gateways",
default or otherwise. With many implementations it is possible
to assign an arbitrary IP address as the default gateway.

I assume that the intent here is to cause the client to arp for
all destination IP addresses whether they are on the local network
or not (i.e. "client side" Proxy ARP). Keep in mind that this is 
an implementation detail as well. BSDish protocol stacks typically 
interpret a 0 metric route with a local IP address as the gateway 
to mean, in effect, that all hosts are on the local network. Obviously
other stacks treat this type of route in a similar way but I don't
think that there is STD RFC that guarantees that behaviour.

Dave Lapp