>> 1) their backbones currently "work" - changing them >> into something which may or may not "work better" is a >> non-trivial operation, and risks the network.
i would disagree. their backbone tend to reach scaling problems, hence the need for bleeding/leading edge technologies. that's been my experience in three past-large networks. > > This is perhaps current. Check back to see large deployments > GSR - sprint/UUNEt > GRF - uunet > Juniper - UUNET/CWUSA indeed, and going back even further is-is, 7000 and the original SSE - mci/sprint vip and netflow - genuity (the original)/probably many others -b