Compute the amplification factor for four services, and the upstream bandwidth an attacker would need to deliver 10 Gbit/s at the victim.

Answer

from fractions import Fraction # (service, bytes the attacker sends, bytes the victim receives) SERVICES = [ ("echo", 60, 60), ("DNS classic", 60, 512), ("DNS with EDNS0", 60, 4000), ("NTP monlist", 234, 48000), ] DELIVERED = 10_000_000_000 # 10 Gbit/s arriving at the victim print("%-16s%9s%14s" % ("service", "factor", "Mbit/s in")) for name, request, response in SERVICES: factor = Fraction(response, request) upstream = Fraction(DELIVERED) / factor print("%-16s%9.1f%14.1f" % (name, float(factor), float(upstream) / 1e6))

Stallings & Brown, Computer Security 5e, ch7 §7.3–§7.5