An algorithm for producing digital signatures, developed by NIST and the NSA. To sign a message, Jean uses the DSA Sign Algorithm to encode a digest of the message using her private key. For all practical purposes, there is no way to decrypt this information. However, anyone who receives the message and accompanying digital signature can verify the signature by using the DSA Verify Algorithm to process the following information: the received signature; a digest of the received message; and Jeans public key. If the output of this algorithm matches a certain part of the digital signature, the signature is valid and the message has not changed. In contrast to RSA and other encryption-based signature algorithms, DSA has no ability to encrypt or decrypt information.