[<< wikipedia] Partitioning Communication System
Partitioning Communication System is a computer and communications security architecture based on an information flow separation policy. The PCS extends the four foundational security policies of a MILS (Multiple Independent Levels of Security) software architecture to the network:

End-to-end Information Flow
End-to-end Data Isolation
End-to-end Periods Processing
End-to-end Damage LimitationThe PCS leverages software separation to enable application layer entities to enforce, manage, and control application layer security policies in such a manner that the application layer security policies are:

Tamper-proofThe result is a communications architecture that allows a software separation kernel and the PCS to share responsibility of security with the application.
The PCS was invented by OIS.  OIS collaborated extensively on the requirements for the PCS with:

National Security Agency
Air Force Research Laboratory
University of Idaho
Lockheed Martin
Rockwell Collins

== References ==
Vanfleet, W. Mark; Luke, Jahn A.; Beckwith, R. William; Taylor, Carol; Calloni, Ben; Unchenick, Gordon (August 2005). "MILS - Architecture for High-Assurance Embedded Computing". Crosstalk (Aug 2005). Archived from the original on 2007-03-19.
Presentation at OMG Software Based Communications Workshop
Beckwith, R. William. "MILS Partitioning Communication System". Objective Interface Systems, Inc. Archived from the original on 2007-09-28.