Building blocks for Threshold FHE

Abstract. The algorithms of Fully Homomorphic Encryption (FHE) schemes are intricate, even under a passive-security model, which is used in state-of-the-art open-source FHE libraries. This talk will describe threshold FHE algorithms and protocols, then discuss the challenges in building and standardizing threshold FHE in an active security model. We suggest a path starting from threshold key generation and threshold decryption, to linearly homomorphic schemes, and finally to fully homomorphic evaluation, and outline some of the challenges associated with these steps, which have to be considered for standardization.

[Slides]