__________ Is a Specification for Cryptographically Signing E-Mail Messages, Permitting

Short Answer

__________ is a specification for cryptographically signing e-mail messages, permitting a signing domain to claim responsibility for a message in the mail stream; message recipients can verify the signature by querying the signer's domain directly to retrieve the appropriate public key and thereby confirming that the message was attested to by a party in possession of the private key for the signing domain.