[toast0]

If you can't handle a few seconds disruption, you really need actually private networking. Dedicated lines (or at least dedicated wavelength on shared fiber) and redundancy and very fast failover.

Volumetric udp reflection isn't really too bad to process anyway, as long as you've got the bandwidth --- fancy tricks get you from the UDP stack dropping useless packets to dropping useless packets without the UDP stack, possibly at the edge without using up nearly as much internal bandwidth.

Where it gets pretty hard to manage would be application level bursts, IMHO.