This National Institute of Standards and Technology Special Publication 800-67, Revision 2: "Recommendations for the Triple Data Encryption Algorithm (TDEA) Block Cipher" specifies the Triple Data Encryption Algorithm (TDEA), including its primary component cryptographic engine, the Data Encryption Algorithm (DEA). When implemented in an SP 800-38 series-compliant mode of operation and in a FIPS 140-2 compliant cryptographic module, TDEA may be used by Federal organizations to protect sensitive unclassified data.