Researchers have dubbed the bit-and-piece Mongol attack a pioneering distributed denial-of-service (DDoS) attack pattern. The approach involves spreading out junk traffic across large numbers of IP addresses in order to evade detection. Nexusguard s Q3 2018 Threat Report found at least 527 Class C networks were impacted in the third quarter alone. The attackers inject small amounts of junk into the legitimate traffic flowing from the IPs, which easily bypass detection thresholds because there’s so little of it per address.
Source: https://threatpost.com/bit-and-piece-ddos-method-emerges-to-torment-isps/141142/