Today I learned about Adaptive DNS Discovery, short ADD, which is an upcoming DNS standard to discover and configure DoH and DoT clients. The idea is that the client learns about a local DoH or DoT server either by Router Advertisement (PvD), well-known entry, an HTTPSSVC or SVCB DNS entry, or a regular alt-svc header for HTTPS.

I learned about this thanks to the webinar by Carsten Strotmann about “Encrypted DNS” in 2020. I also had a follow-up discussion with him about certain aspects that resulted out of the talk on Mastodon.