How Does a Digital Signature Rely on a Cryptographic Hash Function?
A digital signature process begins by hashing the message or document (e.g. a trade instruction) to create a fixed-size digest. The sender then encrypts this hash digest using their private key.
The recipient can verify the signature by decrypting the hash with the sender's public key and independently hashing the received message. If the two hashes match, it proves the message's authenticity and integrity.
The hash function ensures the signature is compact and unique to the document.
Glossar
Hash Function
Function ⎊ A hash function is a mathematical algorithm that takes an input of arbitrary size and produces a fixed-size output, known as a hash value or digest.
Digital Signature
Authentication ⎊ A digital signature, within cryptocurrency, options trading, and financial derivatives, functions as cryptographic attestation of a transaction’s origin and integrity, ensuring non-repudiation for the signatory.
Message Authentication Code
Data Authentication ⎊ A Message Authentication Code is a cryptographic checksum generated using a shared secret key and the message content, appended to the data to ensure both its integrity and authenticity during transmission between two parties.
Cryptographic Hash
Function ⎊ A cryptographic hash is a mathematical algorithm that transforms an input of arbitrary size into a fixed-size string of characters, known as a hash value or digest.
Digital Signature Process
Execution ⎊ The digital signature process involves hashing the transaction data, combining that hash with the private key, and applying the specific mathematical rules of the chosen elliptic curve algorithm to produce the unique signature pair.
Decrypting the Hash
Process ⎊ Decrypting the hash is a common misnomer for the Proof-of-Work mining process, which actually involves finding a specific input value, or nonce, that produces a hash output meeting a predefined difficulty target.