August 26, 1991. John W. Lyons, Director. Digital Signature Standard. The DSA digital signature is a pair of large numbers represented in a computer as strings of binary digits. The DSA includes signature generation and verification.
Generation makes use of a private key to generate a digital signature.
Verification of the signature makes use of a public key which corresponds to, but is not the same as, the private key used to generate the signature. Each user possesses a private and public key pair. Public keys are assumed to be known to all members of a group of users or to the public in general. Private keys must be known only by their creators. Anyone can verify the signature of a user by employing that user's public key.