ADVANCES IN INFORMATION BARRIER DESIGN

The concept of an information barrier, or IB, has been widely discussed for a number of years. An IB is used in a measurement system that contains classified information to prevent the release (either intentional or inadvertent) of the classified information while still allowing an inspecting party to reach independent conclusions as to the contents of a storage container. Typically, an IB would be used in a measurement system regime that requires the owner of certain storage containers to declare the contents of the containers (in unclassified terms) and an inspecting party to confirm this declaration. The IB allows the owner’s declaration to be confirmed without releasing any classified information to the inspecting party. Most IB design concepts are based on two attribute measurement systems (AMSs) that were built and demonstrated in the U.S. in 1999 and 2000. These IBs relied heavily on simple hardware implementations and performed well in a “one-time” demonstration mode. However, implementation of an AMS in a long-term verification regime will place a different set of requirements on the entire AMS system—and the IB, in particular. In this paper, we will concentrate on the effects of changing constraints on IB design, new IB concepts that have been developed since the earlier demonstrations, and design concepts the have been developed within a number of related verification regimes.