Learning with Errors (LWE) problems are the foundations for numerous applications in lattice-based cryptography and are provably as hard as approximate lattice problems in the worst case. Here we present a reduction from LWE problem to dihedral coset problem(DCP). We present a quantum algorithm to generate the input of the two point problem which hides the solution of LWE. We then give a new re...

The Learning with Errors (LWE) problem has gained a lot of attention in recent years leading to a series of new cryptographic applications. Speci cally, it states that it is hard to distinguish random linear equations disguised by some small error from truly random ones. Interestingly, cryptographic primitives based on LWE often do not exploit the full potential of the error term beside of its ...

The Learning with Errors (LWE) problem has become a central building block of modern cryptographic constructions. This work collects and presents hardness results for concrete instances of LWE. In particular, we discuss algorithms proposed in the literature and give the expected resources required to run them. We consider both generic instances of LWE as well as small secret variants. Since for...

One of the most attractive problems for post-quantum secure cryptographic schemes is the LWE problem. Beside combinatorial and algebraic attacks, LWE can be solved by a lattice-based Bounded Distance Decoding (BDD) approach. We provide the first parallel implementation of an enumeration-based BDD algorithm that employs the Lindner-Peikert and Linear Length pruning strategies. We ran our algorit...

The worst-case hardness of finding short vectors in ideals of cyclotomic number fields (Ideal-SVP) is a central matter in lattice based cryptography. Assuming the worst-case hardness of Ideal-SVP allows to prove the Ring-LWE and Ring-SIS assumptions, and therefore to prove the security of numerous cryptographic schemes and protocols — including key-exchange, digital signatures, public-key encry...

Some recent constructions based on LWE do not sample the secret uniformly at random but rather from some distribution which produces small entries. The most prominent of these is the binary-LWE problem where the secret vector is sampled from {0, 1}∗ or {−1, 0, 1}∗. We present a variant of the BKW algorithm for binary-LWE and other small secret variants and show that this variant reduces the com...

This work presents a study of the complexity of the Blum-Kalai-Wasserman (BKW) algorithm when applied to the Learning with Errors (LWE) problem, by providing refined estimates for the data and computational effort requirements for solving concrete instances of the LWE problem. We apply this refined analysis to suggested parameters for various LWE-based cryptographic schemes from the literature ...

Several ideal-lattice-based cryptosystems have been broken by recent attacks that exploit special structures of the rings used in those cryptosystems. The same structures are also used in the leading proposals for post-quantum lattice-based cryptography, including the classic NTRU cryptosystem and typical Ring-LWE-based cryptosystems. This paper proposes NTRU Prime, which tweaks NTRU to use rin...

In this lecture we will see a fuller development of the LWE based homomorphic encryption scheme. The multiplication operation in the naive LWE− HE scheme changes the form of the cipher text. In this lecture we see a dimensionality reduction trick to restore the form of the original ciphertext. Finally we conclude with reductions between LWE assumptions that relax the constraints on the probabil...

We consider the binary-LWE problem, which is the learning with errors problem when the entries of the secret vector are chosen from {0, 1} or {−1, 0, 1} (and the error vector is sampled from a discrete Gaussian distribution). Our main result is an improved lattice decoding algorithm for binary-LWE which first translates the problem to the inhomogeneous short integer solution (ISIS) problem, and...