http://www.rfc-editor.org/rfc/rfc0942.txt
RFC 0942: Transport protocols for Department of Defense data networks, 1985-02-01T23:00:00-00:00This RFC reproduces the National Research Council report resulting from a study of the DoD Internet Protocol (IP) and Transmission Control Protocol (TCP) in comparison with the ISO Internet Protocol (ISO-IP) and Transport Protocol level 4 (TP-4).