Noise Distributions in Homomorphic Ring-LWE [article]

Sean Murphy, Rachel Player
2017 IACR Cryptology ePrint Archive  
In the Ring-LWE literature, there are several works that use a statistical framework based on δ-subgaussian random variables. These were introduced by Miccancio and Peikert (Eurocrypt 2012) as a relaxation of subgaussian random variables. In this paper, we completely characterise δ-subgaussian random variables. In particular, we show that this relaxation from a subgaussian random variable corresponds only to the shifting of the mean. Next, we give an alternative noncentral formulation for a
more » ... bgaussian random variable, which we argue is more statistically natural. This formulation enables us to extend prior results on sums of δ-subgaussian random variables, and on their discretisation.
dblp:journals/iacr/MurphyP17 fatcat:fg6hlhvyenbfjdqls4cg2nxjg4