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Title: Characterization of Anycast Adoption in the DNS Authoritative Infrastructure
Anycast has proven to be an effective mechanism to enhance resilience in the DNS ecosystem and for scaling DNS nameserver capacity, both in authoritative and the recursive resolver infrastructure. Since its adoption for root servers, anycast has mitigated the impact of failures and DDoS attacks on the DNS ecosystem. In this work, we quantify the adoption of anycast to support authoritative domain name service for top-level and second-level domains (TLDs and SLDs). Comparing two comprehensive anycast census datasets in 2017 and 2021, with DNS measurements captured over the same period, reveals that anycast adoption is increasing, driven by a few large operators. While anycast offers compelling resilience advantage, it also shifts some resilience risk to other aspects of the infrastructure. We discuss these aspects, and how the pervasive use of anycast merits a re-evaluation of how to measure DNS resilience.  more » « less
Award ID(s):
1705050 1629973
NSF-PAR ID:
10287364
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Network Traffic Measurement and Analysis Conference (TMA'21)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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