September 8, 2021
UTC timezone
OARConline 35a begins 15:00 UTC today 8 September

Anycast, Inflation, and Efficiency in the Root DNS

Sep 8, 2021, 4:00 PM
Standard Presentation Online Workshop OARConline 35a


Thomas Koch (Columbia University)


Anycast is used to serve content including root DNS. However, prior work examining
root DNS suggests anycast deployments incur significant inflation, with users often routed to suboptimal sites especially for larger deployments. These results are surprising, given the importance and growth of production anycast deployments. We reassess anycast performance -- using new methodology we show root DNS latency hardly matters to users because caching is so effective. We then show inflation in the root DNS is not as poor as previously thought, since recursives can preferentially query their best performing root letter. We conclude with a discussion of how deployment size relates to efficiency and latency, and present survey results from root DNS operators elucidating reasons for expansion of the root DNS.
These results demonstrate the importance of context and coverage when measuring system performance.

Talk Duration 20 Minutes Presentation ( inc 5 Minutes Q&A)

Primary authors

Thomas Koch (Columbia University) Calvin Ardi (USC/ISI) Ethan Katz-Bassett (Columbia Univeristy) Matt Calder (Microsoft) John Heidemann (USC/ISI) Ke Li (Columbia University)

Presentation materials