A big thanks to tevador from TorProject Proof of Work for .onion Services https://spec.torproject.org/hspow-spec/
The overall denial-of-service prevention strategies in Tor are described in the Denial-of-service prevention mechanisms in Tor document. This document describes one specific mitigation, the proof-of-work client puzzle for onion service introduction.
This was originally proposal 327, A First Take at PoW Over Introduction Circuits authored by George Kadianakis, Mike Perry, David Goulet, and tevador.
From the Video "State of the Onion 2023"
DuckDuckGo Video-Search: https://duckduckgo.com/?q=DhdFL0kXu440+state+of+the+onion&iar=videos&iax=videos&ia=videos&iai=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DhdFL0kXu440
Youtube: https://www.youtube.com/watch?v=hdFL0kXu440
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