Dallas-based Revere Security, a developer of cryptographic data security software, said late last week that it has named cryptography expert Whitfield Diffie as the firm's Chief Cryptographer. Diffie is the co-inventor of the widely used Diffie-Hellman protocol, which is used for public key cryptography. Diffie was most recently Chief Security Officer at Sun Microsystems, and also has served at Northern Telecom and Stanford. Revere Security develops highly efficient algorithms designed for embedded devices, which typically are unable to handle the complex calculations and computing power needed for other encryption schemes and algorithms. The firm said that Diffie has been an advisor to the firm for the last year.