Darren Reed <darrenr@reed.wattle.id.au> writes:

> In some email I received from Jens A Nilsson, sie wrote:
> > 
> > I don't understand "ifconfig lo0 127.0.0.1 netmask 0xffff0000"
> > changes the netmask correctly.
> 
> Why should changing the netmask require you to specify the IP# ?

If interfaces connected to media rather than making the IP address a
property of the media, there wouldn't be a need to specify it.

IMHO, it should be:

{physical} <-> {logical interface} <-> {kernel}

rather than

{physical interface with aliases} <-> {kernel}

The former allows me to track exactly how much traffic comes in on a
given IP address, for instance.  I suspect it would also make some
routing issues simplier, like when more than one subnet exists on a
single wire.

It would also allow a trivial way to bond two physical interfaces into
one, for speed or whatever.

--Michael