On 9 Nov 2014, at 10:12, Jon Lewis wrote:
The tricky part is when to remove the route...since you can't tell if the attack has ended while the target is black holed by your upstreams.
You can with NetFlow, if you've D/RTBHed the IP in question on your own infrastructure. NetFlow reports statistics on dropped traffic (except on a few platforms with implementation deficiencies).
But this kind of thing punishes the victim. It's far better to do everything possible to *protect* the target(s) of an attack, and only use D/RTBH as a last resort.
----------------------------------- Roland Dobbins <rdobb...@arbor.net>