Ethereum's 2023 ceremony in which about 141,000 people helped generate KZG parameters. One honest participant is enough.
The idea: These proof systems need public numbers built from a secret τ, so that provers can do math "at τ" without knowing it. Whoever knew τ could fake proofs, so it must be destroyed. A ceremony makes that easy to trust: each participant mixes in their own secret randomness, so the final τ is effectively the combination of all of them, and it stays unknown as long as a single participant threw their piece away.
Why it matters: Blob commitments are safe as long as one contributor destroyed their secret.
On the map: ≥ 1 of ~141,000 contributions destroyed its secret
KZG commitments need public parameters derived from a secret τ that nobody may know. Ethereum's KZG ceremony (2023) collected about 141,000 contributions[1] from anyone who wanted to take part, through a website.
The parameters are safe if at least one contribution was generated honestly and then destroyed, a very mild assumption with so many participants. Someone who knew τ could forge blob openings.
If any of these breaks, this breaks too.
If this breaks, these break with it.