Mastering Blockchain - Second Edition

RSA digital signature algorithm

The following is the RSA digital signature algorithm:

1. Calculate the hash value of the data packet: This will provide the data integrity guarantee as the hash can be computed at the receiver's end again and matched with the original hash to check whether the data has been modified in transit. Technically, message signing can work without hashing the data first, but is not considered secure.
2. Signs the hash value with the signer's private key: As only the signer has the private key, the authenticity of the signature and the signed data is ensured.

Digital signatures have some important properties, such as authenticity, unforgeability, and nonreusability. Authenticity means that the digital signatures are verifiable ...