Your statement makes something of a presumption
as to the architecture of a network. In many
networks, edge aggregation devices do not
participate in backbone routing, but simply
pass the traffic they are aggregating into the core.
My first reaction, as well. However, I was reminded
by Andrew Odlyzko that the cable tv industry's (MSOs')
peering universe constitute a form of flattened 'edge',
if one were to consider the larger Internet's core
against the MSO community, which makes for another
form of interesting analysis, since much of today's
(especially more capacious) residential "broadband"
flows begin and end on MSOs' networks, and sometimes
never touch the larger core, fwiw. And this opens the
door to other forms of "walled garden" environments,
including intranets, some providers' CDNs, extranets,
and so on.
Frank A. Coluccio
DTI Consulting Inc.
On Sun Feb 18 10:54 , Andrew Lee sent: