Prototyping SP4: a Secure Data Network System Transport Protocol Interoperability Demonstration Project

The NIST Secure Data Network System (SDNS) project implements computer to computer communications security for distributed applications. The internationally accepted Open Systems Interconnection (OSI) computer networking architecture provides the framework for SDNS, which is a project of the National Security Agency (NSA). SDNS utilizes the layering principles of OSI to implement secure data transfers between computer nodes of local area and wide area networks. SDNS implements SP4, a security protocol at the OSI Transport layer (layer 4) that provides end-to-end reliable transparent data communications with confidentiality and integrity security services. Laboratory prototypes of SP4 formed the basis of proposed voluntary national standards and will form the basis for future security enhancements for the Government Open Systems Interconnection Profile (GOSIP).