Anycast has been extensively used by DNS Root Server operators to improve performance, resilience, and reliability. In line with the migration towards IPv6 networks, 9 out of 11 anycasted Root Servers are running on both IPv4 and IPv6 (dual-stack mode) today. Ideally, both protocols should provide similar performances. Problem arises since operators may have different peering policies for IPv4 and IPv6 networks, which leads to different catchment areas for the same service and potentially different quality of service. In this thesis, we analyze the IPv4 and IPv6 catchments of anycasted Root Servers from control-plane perspective between February 2008 to June 2016 using BGP data from RIPE RIS. We study the evolution and the differences of the catchment areas over the time. We also develop visualization tool to help operator assess their catchment areas. While we specifically study DNS Root Server, our methodology can be applied to other anycast services as well.
