I've heard it said that if you stand up a new DHT it will be subject to Sybil attack until it gets very very large, and so the only reasonable DHT is Mainline DHT since it is already large enough to withstand this.

This is true for a Kademlia DHT. But with newer DHT research it is no longer true (for example, Whanau). And there has been about 20 years of research since Kademlia, and the Internet has changed too (NAT is even more of a problem now), plus I have a few other reservations like mutable data must be very small, disappears rather quickly, isn't fixed into the protocol yet (many nodes don't participate) and it also feels like an abuse of a DHT that was meant for bittorrent (just like inscriptions/ordinals/NFTs feels like an abuse of bitcoin).

I think it is worth researching DHT technology further, but of course mainline DHT might still be the right answer, I'm just not convinced given the concerns I've mentioned.

Nonetheless, pkarr is pretty fucking cool. The rest of pubky looks to me like an attempt to do something interesting with pkarr.

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