Abstract: System and method for generating an electronic signature to authenticate data includes generating a private and a public key using the last value in a hash chain formed from the private key as a starting point, signing a message m, using a distinct set of hash chains using a second secure hash value of the message m and a counter c, selecting a block offset using the hash value of the selected chains, the message m, and the counter c, generating the signature from the selected seals and the counter. The electronic signature validity is verified by synchronizing a verification unit with a source of a signed message, computing expected chains by hashing the signed message m and a counter c with a first hash function, computing a set of expected block offsets by hashing the signed message m, counter c, and computed chains with a second hash function.