Optimizing DNS Resolvers for High Loads

Handling volumetric attacks and high loads is fundamental for Domain Name System (DNS) resolvers. While one can often scale up resources to cope with high loads, this costly solution is not always viable. Thus, our work revisits the design of DNS resolvers and maps the design decisions that most impact the resolver's robustness to high loads and volumetric attacks. Our work suggests a novel resolver composed of deadline-aware queue management, optimized cache policy, and high-load handling mechanisms. An evaluation with real DNS traces shows a consistent improvement of 21% in a high load scenario and by 40% under an NXDomain attack when compared with the best alternative method.