RE: network controls are necessary

["Christian Huitema" <huitema@windows.microsoft.com>]

> I have nothing to gain by having control in the SBR.  I no longer work
> at Cisco, so I have no interest in placing more responsibility and
> complexity into the CPE gear.  I'm just trying to design a clean
> architecture
> that scales.  That's what we should all be striving for.

I have heard many assertions that this or that solution does not scale.
Since we are engineers, I would very much like that references to
scaling be backed up by a complexity analysis. Lacking that, we are
dealing with beliefs and esthetics.

For example, we can say that, with CIDR, the size of the routing tables
in the DFZ routers should scale as something between O(P), which is the
number of DFZ providers, which itself is expected to scale with the
number of sites as something like either O(log S) or O(sqrt S),
depending which opinion you believe. On the other hand, without CIDR,
the routing tables would scale as O(S). That makes the comparison quite
clear.

-- Christian Huitema