Nested Hybrids

Abstract: Hybrid arguments are a popular proof technique in cryptography. In this talk I'll show a variant of this technique where the arguments are constructed iteratively rather than in the usual sequential way. I'll show two applications of this techniques based on the papers "Adaptive Security of Constrained PRFs" (Asiacrypt 2014) and "A Quasipolynomial Reduction for Generalized Selective Decryption on Trees" (Crypto 2015).