Content delivery networks (CDNs) commonly use DNS to map end-users to the best edge servers. A recently proposed EDNS0-Client-Subnet (ECS) extension allows recursive resolvers to include end-user subnet information in DNS queries, so that authoritative DNS servers, especially those belonging to CDNs, could use this information to improve user mapping. In this paper, we study the ECS behavior of ECS-enabled recursive resolvers from the perspectives of the opposite sides of a DNS interaction, the authoritative DNS servers of a major CDN and a busy DNS resolution service. We find a range of erroneous (i.e., deviating from the protocol specification) and detrimental (even if compliant) behaviors that may unnecessarily erode client privacy, reduce the effectiveness of DNS caching, diminish ECS benefits, and in some cases turn ECS from facilitator into an obstacle to authoritative DNS servers' ability to optimize user-to-edge-server mappings.
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Physicochemical Properties of ECS Supports and Pt/ECS Catalysts
- Award ID(s):
- 1919280
- NSF-PAR ID:
- 10344928
- Date Published:
- Journal Name:
- ACS Applied Energy Materials
- Volume:
- 4
- Issue:
- 9
- ISSN:
- 2574-0962
- Page Range / eLocation ID:
- 9111 to 9123
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsaem.1c01392
