Year
2017
Abstract
?Procedures and techniques to confirm upper limits on the number ofnuclear warheads will become a key verification objective should future arms-controlagreements place limits on the total number of nuclear weapons in the arsenals. Thiswould require baseline declarations, and the challenge would then be to confirm theircorrectness and completeness. So far, most states remain reluctant to make baselinedeclarations, however, and ways ought to be found to encourage steps at an early date.Here, we explore a cryptographic escrow scheme that would both provide a secureinformation-sharing mechanism and a basis to confirm numerical limits without usingtagging techniques. It leverages well established cryptographic primitives, in particularcommitment schemes. Such schemes allow a party to commit to a particular piece ofinformation, or value, while keeping it hidden from others. The value can be released ata later stage while ensuring other parties it was not altered. Cryptographic commitmentsto declaration can use a hash (or “message digest”) that is much shorter than the messageitself. Our escrow could have two distinct but equally important roles. First, it wouldcommit weapon states to the current status of their nuclear arsenal (including, forexample, warhead numbers, types, and storage locations) without having to make thisinformation public at this time. Having these records available later on couldsignificantly increase the confidence in a future verification regime because a weaponstate could demonstrate the history or “provenance” of particular treaty accountableitems. Second, such declarations could also lay the basis for future verificationapproaches that do not rely on tagging treaty accountable items at all. Instead, hostcountries would reveal cleartext for selected entries as needed, and inspections wouldthen confirm the consistency between the declared and the actual inventory of treatyaccountable items at a particular site.