GOSIP

The Government Open Systems Interconnection Profile (GOSIP) was a specification that profiles open networking products for procurement by governments in the late 1980s and early 1990s.

In practice, from 1995 interest in OSI implementations declined, and worldwide the deployment of standards-based networking services since have been predominantly based on the Internet protocol suite. However, the Defense Messaging System continued to be based on the OSI protocols X.400 and X.500, due to their integrated security capabilities.

...
Wikipedia