Information barriers

Full text: An information barrier (IB) consists of procedures and technology that prevent the release of sensitive information during a joint inspection of a sensitive nuclear item, and provides confidence that the measurement system into which it has been integrated functions exactly as designed and constructed. Work in the U.S. on radiation detection system information barriers dates back at least to 1990, even though the terminology is more recent. In January 1999 the Joint DoD-DOE Information Barrier Working Group was formed in the United States to help coordinate technical efforts related to information barrier R and D. This paper presents an overview of the efforts of this group, by its Chairs, as well as recommendations for further information barrier R and D. Progress on the demonstration of monitoring systems containing IBs is also provided. From the U.S. perspective, the basic, top-level functional requirements for the information barrier portion of an integrated radiation signature-information barrier inspection system are twofold: The host must be assured that his classified information is protected from disclosure to the inspecting party; and The inspecting party must be confident that the integrated inspection system measures, processes, and presents the radiation-signature-based measurement conclusion in an accurate and reproducible manner. It is the position of the United States that in the absence of any agreement to share classified nuclear weapons design information in the conduct of an inspection regime, the requirement to protect host country classified warhead design information is paramount and admits no tradeoff versus the confidence provided to the inspecting party in the accuracy and reproducibility of the measurements. The U.S. has reached an internal consensus on several critical design elements that define a general standard for radiation signature information barrier design. These criteria have stood the test of time under intense policy and security reviews. These elements are: Supplier of Integrated Measurement System and Information Barrier; Central Processing Units (CPUs); Non-CPU Equipment; Procedures; Electronic Emanations; Location of Barriers(s); Software, Firmware, CPU Operating Systems; Storage, Authentication, and Disposition of Data and Data Media; Inputs and Outputs. Technical specialists from cooperating parties must be able to prove to their respective policy makers that it is not overly difficult to make measurements of sensitive objects without revealing classified information. Without technical measures to inspect classified nuclear items and materials, it will be extremely difficult to reduce stockpiles in a manner that does not impact the security of Russia and the United States. The importance of successfully developing and implementing effective information barrier methods and procedures can not be overstated. A cooperative program is a good investment in U.S., Russian, and international security and threat reduction. The utility of radiation detection systems to characterize known and unknown quantities of nuclear material is without dispute. Such systems offer a powerful technological tool for warhead dismantlement transparency, and bilateral and international safeguards. There are many examples of their use in the international community today. The problem is the application of such systems with a host country's sensitive nuclear material. If it is one objective of any bilateral or trilateral arrangement to prevent the release of classified nuclear data to the inspecting party when inspecting sensitive materials, then some form of information barrier must be integrated into the measurement system. Through a set of well-defined principles as described above, the protection of such information is not a difficult problem to solve. Perhaps the more difficult problem is providing an inspecting party with confidence, for the case where the host supplies and/or certifies the measurement equipment, that the system is functioning properly and does not incorporate any hidden features (or 'switches') that allows the host to pass out-of-spec items. Authentication of information barrier systems is an extremely important concept to consider in designing and assembling these types of inspection systems. There are a limited set of straightforward approaches to authenticate such systems, when applied in conjunction with open and cooperative system design and fabrication, that will provide a high degree of confidence to both host and inspector that the system will prevent the release of classified information and yet still inspect items in a manner consistent with the objectives of an inspection agreement. These principles have been outlined in this paper, along with areas where additional studies would be helpful. (author)