SDN - Secure Data Networks
Standards published by National Security Agency. They are not publically available. They provide some of the security standards used in MMHS.
| SDN 701 | Message Security Protocol (MSP) |
| SDN.703 | MISSI Management Protocol (MMP) |
| SDN 705 | Strong Authentication for X.400, X.500, and X.700 |
| SDN 706 | X.509 Certificate and CRL Profiles and Certificate Path Processing Rules for MISSI |
| SDN 801 | Access Control Concepts and Mechanisms |
