Archived article · Original source date: 2024-08-01
This article is preserved from the previous Solana Bulls site as a historical archive. It reflects its original context; references to products, people, market conditions, eligibility, or rules may no longer be current.
A simple example is proving knowledge of a secret that satisfies a public condition without sending the secret itself. Real systems express the condition mathematically and use a proof protocol whose security depends on defined assumptions.
Statement, witness, prover, and verifier
The statement is the public claim. The witness is the private information that makes the claim true. The prover constructs evidence from both, and the verifier checks the evidence using the protocol's public parameters and inputs.
Three core properties
- Completeness: an honest prover with a valid witness should convince an honest verifier.
- Soundness: a prover should not be able to convince the verifier of a false statement except with a bounded probability under the security model.
- Zero knowledge: the verifier should learn no more about the witness than the protocol is designed to reveal.
Interactive and non-interactive proofs
Some protocols require multiple challenges and responses. Non-interactive systems produce a proof that can be checked later, often using a common reference string, a random-oracle model, or other setup. SNARKs and STARKs are broad families with different tradeoffs, not interchangeable product labels.
What zero knowledge does not mean
A proof is not the same as encryption, anonymity, secure storage, trusted input data, or end-to-end application privacy. Public inputs, outputs, wallet addresses, timing, network metadata, deposits, withdrawals, and application behavior may still reveal sensitive information.
Applications and limitations
Zero-knowledge systems can support validity proofs, selective disclosure, private membership checks, authentication, and confidential application logic. They also introduce circuit correctness, parameter generation, proving cost, verifier, upgrade, side-channel, data-availability, and user-experience risks.
Solana context
Solana applications may verify or generate proofs for application-specific purposes, subject to program support and compute constraints. The base network remains public by default, and a proof-enabled application must document exactly which fields are hidden, which are public, and who can recover or audit them.
Evaluate the concrete protocol, circuit, proof system, verifier implementation, public inputs, setup, audits, and upgrade authority rather than assuming the phrase zero knowledge supplies universal privacy or security.