Meaning
A trusted third-party service issues digital certificates that link a specific piece of data to a verified date and time. The timestamp authority provides an independent record that a document existed in a certain state at a precise moment. This evidence is required for intellectual property claims and the execution of smart contracts.
Cryptographic Binding
The service receives a hash of the file and signs it with its own private key. This signature includes a time value taken from a high-precision clock such as an atomic time source. Because the authority only sees the hash, the privacy of the original document is maintained throughout the process.
It acts as a digital notary for the modern era.
Audit Trail
Public logs of issued timestamps allow any party to verify the validity of a record. This removes the need to trust the creator of the file.
Verification Protocol
Checking the validity of a timestamp involves using the public key of the authority to decrypt the signature. If the resulting hash matches the current state of the file, the time and the content are proven to be authentic. This process requires a continuous connection to the certificate revocation list of the authority.