DNS Flag Day 2020
Oct 2, 2020Christian Elmerot
Summary
This post details Cloudflare's compliance with DNS Flag Day 2020, which focuses on reducing IP fragmentation of DNS packets. Cloudflare already enforces reasonable DNS message size limits over UDP and ensures availability over TCP, making its services compliant without further action. The post explains the problem of UDP fragmentation, the importance of EDNS0 and DNSSEC, and the role of TCP for larger DNS messages.
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