It was presumably done over UDP where it&#x27;s trivial to fake source IP. What&#x27;s the minimum size of a valid UDP-based DNS request? Let&#x27;s guesstimate 25 bytes. Then 50M&#x2F;s * 25 bytes = 1.25 GB&#x2F;s. Or 10 Gbit&#x2F;s.<p>Is that really so impressive these days?