Halo

Basics

• From Token Economy #106:

"Recursive zero-knowledge proofs with no trusted setup.

Pretty mind-blowing progress in ZK-land lately. The latest breakthrough comes from the Electronic Coin Company team (who launched and supports Zcash), who have uncovered how to achieve practical zero-knowledge recursive proof composition *without* requiring a trusted setup.

Recursive proof composition is very Inception-y, where a proof verifies the correctness of another instance of itself. Meaning one only needs one proof to verify an entire blockchain potentially, or any amount of computational effort really. The implication is that this design (aka 'nested amortization') eliminates completely the need for a trusted setup, *while* obviously still delivering on scalability."

• Whitepaper can be found here and a statement by the ECC on their new setup over here (10-9-2019).