[W/K] :: digital signature

  digital signature
       
           Extra data appended to a message which
          identifies and authenticates the sender and message data using
          public-key encryption.
       
          The sender uses a one-way hash function to generate a
          hash-code of about 32 bits from the message data.  He then
          encrypts the hash-code with his private key.  The receiver
          recomputes the hash-code from the data and decrypts the
          received hash with the sender's public key.  If the two
          hash-codes are equal, the receiver can be sure that data has
          not been corrupted and that it came from the given sender.
       
          (1995-02-07)