Meaning
Cryptographic protocol requiring a party to commit to a specific value while keeping it hidden, with the ability to reveal it later. A hash commitment prevents the committing party from changing the value once the initial hash has been shared. It is a fundamental building block for secure voting and sealed-bid auctions.
Temporal Proof
Publishing the digest of a document today proves its existence even if the full text is not released until a later date. This hash commitment functions as a marker in time that cannot be moved or altered. It allows for the verification of a claim without premature disclosure of trade secrets.
Verification Phase
When the time comes to reveal the committed value, the sender provides the original data and a secret key. The receiver then hashes these components to see if the result matches the previous hash commitment exactly. If the two values align, the receiver knows the data is authentic and was not swapped after the commitment was made.
This two-step process ensures that a founder cannot retroactively adjust a recorded promise. The math behind the protocol ensures that finding a different input that produces the same hash is practically impossible.
Dispute Resolution
This mechanism provides an objective way to settle disagreements about when a specific decision was reached.
