[Originally published as Federal Standard 1028 (FED-STD-1029) by the General Services Administration. Note on Cover: "Federal Standard 1028 has been redesignated as Federal Information Processing Standards Publication (FIPS PUB) 141." Per Federal Register Notice FR 53 41221, October 20, 1988.]

This standard specifies interoperability and security related requirements for the use of encryption with CCITT (i.e. International Telegraph and Telephone Consultative Committee) Group 3-type facsimile equipment. The algorithm used for encryption is the Data Encryption Standard (DES), described in Federal Information Processing Standards Publication 46. Requirements contained in section 3 below relate to the interoperation of DES Cryptographic Equipment, or their operation with associated CCITT Group 3 facsimile equipment. Additional security requirements, not directly relating to interoperability, are contained in Federal Standard 1 027.