ZK-SNARK
A compact cryptographic proof that confirms a statement is true while revealing nothing about the underlying data.
The acronym stands for Zero-Knowledge Succinct Non-interactive Argument of Knowledge. The proof is tiny and fast to verify, even when the computation behind it was huge. Zcash used SNARKs for shielded transactions; many ZK-rollups use them to prove that a batch of transactions executed correctly.
The historical weakness is the trusted setup. Generating the proving keys requires secret randomness that, if kept rather than destroyed, could forge proofs. Modern systems reduce this risk with multi-party ceremonies. SNARKs also lean on elliptic-curve assumptions that a future quantum computer might break.
Related terms
A cryptographic method that proves a statement is true without revealing the underlying data behind it.
ZK-STARKA zero-knowledge proof system that needs no trusted setup and stays secure against quantum attacks, at the cost of larger proofs.
Validity ProofA cryptographic proof submitted with every rollup batch that mathematically guarantees the new state was computed correctly.
zk-RollupA rollup that posts a cryptographic validity proof for every batch, giving near-instant finality on the base chain.