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105 points venusgirdle | 1 comments | | HN request time: 0.21s | source
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adamrmcd ◴[] No.43235014[source]
Neat idea, but my takeaway is I had no idea that DNS also runs on UDP/53.. I always thought it was TCP only! #TIL

The author cites it as performance reasons, but at this scale, even the uplink to cloudflare, would be negligible, no?

replies(4): >>43235271 #>>43235315 #>>43235633 #>>43239993 #
1. teruakohatu ◴[] No.43235315[source]
With 'normal' DNS, UDP with the default and TCP is used if the packet size becomes too large. There are other TCP-only variants such as DoT (DNS over TLS) and DoH (DNS over HTTPS).

I don't think the performance would matter much with some basic caching (or even just OS-level caching), but there is limited memory in an ESP so maybe that is it. I have never noticed issues with DoT and DoH which are theoretically much heavier protocols.