Explainer: Blackhole routing, rate limiting and other strategies used against DDoS cyberattack – Times of India

In our previous article, we explained about a DDoS or a Distributed-Denial-of-Service cyberattack, what it is, how it is carried out and how you can recognise that your internet service is a victim of such an attack. Here, we throw some light on the strategies used by cyber experts to mitigate a DDoS cyberattack. These include Blackhole Routing, Rate Limiting, Web Application Firewall and Anycast Network Diffusion. Let’s go over them one by one.
Blackhole routing
If it is established that an internet property is under a DDoS attack, then the internet service provider (ISP) of that property may create a null route or a blackhole and dump or funnel all the network traffic into it, both legit and malicious. This technique is not the most helpful one as it makes the network inaccessible, something that the hackers want.
Rate limiting
This is a preventive measure, a defensive technique used against DDoS attacks. By Rate limiting, we mean reducing or limiting the number of requests an internet server can accept in a certain time period. While this method may not be powerful enough to handle a complex DDoS cyberattack on its own, it certainly helps in slowing down the hackers from stealing information by making their job more difficult.
Web application firewall
A Web Application Firewall (WAF) is put between the internet and the origin server, and thus it can protect the server from attacks by acting as a reverse proxy. The firewall helps filter the requests the origin server receives.