To defend against such attacks, ISPs employ blackholing techniques. When a DDoS attack is detected, the network operator uses the Border Gateway Protocol (BGP) blackhole feature to discard the traffic destined for the attacked IP addresses. This effectively steers the attack traffic into a “black hole,” preventing it from reaching its intended target.
Blackholing serves as an effective technique because it allows ISPs to quickly and efficiently mitigate the effects of DDoS attacks. By discarding traffic at the network edge, blackholing reduces the performance impact on the network infrastructure and allows legitimate traffic to flow smoothly.
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