Trait concrete_core::specification::entities::LweCiphertextEntity

source · [−]
pub trait LweCiphertextEntity: AbstractEntity<Kind = LweCiphertextKind> {
    fn lwe_dimension(&self) -> LweDimension;
}
Expand description

A trait implemented by types embodying an LWE ciphertext.

Formal Definition

LWE Ciphertext

An LWE ciphertext is an encryption of a plaintext. It is secure under the hardness assumption called Learning With Errors (LWE). It is a specialization of GLWE ciphertext.

We indicate an LWE ciphertext of a plaintext $\mathsf{pt} \in\mathbb{Z}_q$ as the following couple: $$\mathsf{ct} = \left( \vec{a} , b\right) \in \mathsf{LWE}^n_{\vec{s}}( \mathsf{pt} )\subseteq \mathbb{Z}_q^{(n+1)}$$ We call $q$ the ciphertext modulus and $n$ the LWE dimension.

LWE dimension

It corresponds to the number of element in the LWE secret key. In an LWE ciphertext, it is the length of the vector $\vec{a}$. At encryption time, it is the number of uniformly random integers generated.

Required Methods

Returns the LWE dimension of the ciphertext.

Implementors