Towards Standardization of Threshold Schemes at NIST

The Computer Security Division at the National Institute of Standards and Technology (NIST) is taking steps towards the standardization of threshold schemes for cryptographic primitives. These schemes, applicable to single-device and multi-party implementations, are designed with multiple components in a way to enable essential security properties even when up to a certain threshold number of the components are compromised. This offers a path to mitigate attacks on the implementations and operations of cryptographic primitives, and therefore enhance their security. Properties of interest include secrecy of keys (including resistance against side-channel attacks that exploit leakage from real implementations), integrity of computed values, and availability of operations. The first part of the talk will overview two introductory elements of the Threshold Cryptography project: the NIST Internal Report on "Threshold Schemes for Cryptographic Primitives - Challenges and Opportunities in Standardization and Validation of Threshold Cryptography" (NISTIR 8214), which advanced a characterization of threshold schemes and positioned several representative questions relevant to the standardization process; and the "NIST Threshold Cryptography Workshop" (NTCW) 2019, which brought together stakeholders to share perspectives from industry, academia and government. These two steps were helpful to reflect and gain insights for developing a roadmap. The talk will then present a perspective about the challenges and opportunities in moving forward with driving an effort to standardize threshold schemes. The roadmap ahead involves selecting focus areas and items, and will span several phases. Correspondingly, this talk will overview several considerations about criteria to develop for calls for contributions, the balance of flexibility and granularity of possible elements to standardize, and possible ways of collaborating with stakeholders in an open and transparent process towards new standards.