Blackholing involves diverting unwanted traffic destined for a specific IP address or range of addresses to a “black hole,” where it is effectively dropped and no longer reaches its intended target. This approach is particularly useful in mitigating large-scale distributed denial-of-service (DDoS) attacks, where a high volume of traffic floods a network infrastructure, overwhelming its resources and rendering legitimate services inaccessible to users.

Another technique utilized for blackholing is blackhole filtering. In this approach, network operators establish filtering rules at network border routers to identify and filter out malicious traffic before it reaches the intended target. By applying these filters, ISPs can effectively shield their network infrastructure from DDoS attacks and other forms of unwanted traffic.

More info: What are Managed Network Services?