MR-DNS: Multi-resolution Domain Name System

Users want websites to deliver rich content quickly. However, rich content often comes from separate subdomains and requires additional DNS lookups, which negatively impact web performance metrics such as First Meaningful Paint Time, Page Load Time, and the Speed Index. In this paper we investigate the impact of DNS lookups on web performance and propose Multi-Resolution DNS (MR-DNS) to reduce DNS resolutions through response batching. Our results show that MR-DNS has the potential to improve Page Load Time around 14% on average, Speed Index around 10% on average and reduce DNS traffic around 50%. We also discuss how these gains may be realized in practice through incremental changes to DNS infrastructure.