A Simple Provably Secure Key Exchange Scheme Based on the Learning with Errors Problem.

Jíntai Ding

Published Jan 1, 2012• 216 citations

Abstract

Abstract. We use a variant of learning with errors (LWE) problem, a simple and direct extension of the original LWE problem to the case of a small secret, which we call a small LWE problem (SLWE), to build a new simple and provably secure key exchange scheme. The basic idea behind the construction can be viewed as certain type of bilinear pairing with errors (PE). We build a more efficient implementation of our scheme using a similar LWE problem but solely based on matrices, and we extend our construction further using the ring LWE problem, where the provable security is based on the hardness of the ring LWE problem. 1

Related papers

a key exchange scheme based on lattice

Wulu Li

We construct a key exchange scheme with session key security and Alice's privacy, assuming the hardness of "small integer solution" (SIS) problem and "learning with errors" (LWE) problem, which have worst-case to average-case reductions from lattice problems. Our key exchange scheme is the first lattice-based key exchange scheme with provable security. Moreover, our scheme can be modified to be secure under impersonation attack by adding an authentication step, also, it can be modified to be more efficient using a new variant of LWE.

IEEE Intl Conf on Dependable, Autonomic and Secure Computing, Intl Conf on Pervasive Intelligence and Computing, Intl Conf on Cloud and Big Data Computing, Intl Conf on Cyber Science and Technology Congress (DASC/PiCom/CBDCom/CyberSciTech)Dec 1, 20132 citations

Provably Secure LWE Encryption with Smallish Uniform Noise and Secret

Daniel Cabarcas, Florian Göpfert, Patrick Weiden

Abstract. In this paper we propose the first provably secure public key encryption scheme based on the Learning with Errors (LWE) problem, in which secrets and errors are sampled uniformly at random from a relatively small set rather than from the commonly used discrete Gaussian distribution. Using a uniform distribution, instead of a Gaussian, has the potential of improving computational efficiency a great deal due to its simplicity, thus making the scheme attractive for use in practice. At the same time our scheme features the strong security guarantee of being based on the hardness of worst-case lattice problems. After presenting the construction of our scheme we prove its security and propose asymptotic parameters. Finally, we compare our scheme on several measures to one of the most efficient LWE-based encryption schemes with Gaussian noise. We show that the expected efficiency improvement is debunked, due to the large blow-up of the parameter sets involved.

Jan 1, 20142 citations

Provably secure LWE encryption with smallish uniform noise and secret

Daniel Cabarcas, Florian Göpfert, Patrick Weiden

In this paper we propose the first provably secure public key encryption scheme based on the Learning with Errors (LWE) problem, in which secrets and errors are sampled uniformly at random from a relatively small set rather than from the commonly used discrete Gaussian distribution. Using a uniform distribution, instead of a Gaussian, has the potential of improving computational efficiency a great deal due to its simplicity, thus making the scheme attractive for use in practice. At the same time our scheme features the strong security guarantee of being based on the hardness of worst-case lattice problems. After presenting the construction of our scheme we prove its security and propose asymptotic parameters. Finally, we compare our scheme on several measures to one of the most efficient LWE-based encryption schemes with Gaussian noise. We show that the expected efficiency improvement is debunked, due to the large blow-up of the parameter sets involved.

ACM ASIA Public-Key Cryptography Workshop (APKC)May 30, 201410 citations

Provably Secure LWE-Encryption with Uniform Secret

Daniel Cabarcas, Florian Göpfert, Patrick Weiden

In this paper we propose the first provably secure public key encryption scheme based on the Learning with Errors (LWE) problem, in which secrets and errors are sampled uniformly at random from a relatively small set rather than from the commonly used discrete Gaussian distribution.Using a uniform distribution, instead of a Gaussian, has the potential of improving computational efficiency a great deal due to its simplicity, thus making the scheme attractive for use in practice.At the same time our scheme features the strong security guarantee of being based on the hardness of worst-case lattice problems.After presenting the construction of our scheme we prove its security and propose asymptotic parameters.Finally, we compare our scheme on several measures to one of the most efficient LWE-based encryption schemes with Gaussian noise.We show that the expected efficiency improvement is debunked, due to the large blow-up of the parameter sets involved.

Mar 21, 20131 citation

Securely Instantiating Cryptographic Schemes Based on the Learning with Errors Assumption

Florian Göpfert

Since its proposal by Regev in 2005, the Learning With Errors (LWE) problem was used as the underlying problem for a great variety of schemes. Its applications are many-fold, reaching from basic and highly practical primitives like key exchange, public-key encryption, and signature schemes to very advanced solutions like fully homomorphic encryption, group signatures, and identity based encryption. One of the underlying reasons for this fertility is the flexibility with that LWE can be instantiated. Unfortunately, this comes at a cost: It makes selecting parameters for cryptographic applications complicated. When selecting parameters for a new LWE-based primitive, a researcher has to take the influence of several parameters on the efficiency of the scheme and the runtime of a variety of attacks into consideration. In fact, the missing trust in the concrete hardness of LWE is one of the main problems to overcome to bring LWE-based schemes to practice. This thesis aims at closing the gap between the theoretical knowledge of the hardness of LWE, and the concrete problem of selecting parameters for an LWE-based scheme. To this end, we analyze the existing methods to estimate the hardness of LWE, and introduce new estimation techniques where necessary. Afterwards, we show how to transfer this knowledge into instantiations that are at the same time secure and efficient. We show this process on three examples: - A highly optimized public-key encryption scheme for embedded devices that is based on a variant of Ring-LWE. - A practical signature scheme that served as the foundation of one of the best lattice-based signature schemes based on standard lattices. - An advanced public-key encryption scheme that enjoys the unique property of natural double hardness based on LWE instances similar to those used for fully homomorphic encryption.

Jan 1, 20162 citations

New Authenticated Key Exchange Scheme Based on Ring Learning with Errors Problem

Xiaopeng Yang, Wenping Ma, Chengli Zhang

Using the hard assumption of Ring-Decision Learning With Errors (Ring-DLWE) in the lattice, a new Authenticated Key Exchange (AKE) scheme is proposed, which is based on the Peikert's reconciliation technique. Under the standard model, the proposed scheme is provably secure in the CK model, which is additionally achieves weak Perfect Forward Secrecy (wPFS). Compared with the current Key Exchange (KE) schemes based on the LWE, the proposed scheme not only protects the shared session key with balanced key derivation function but also resists quantum attacks because of the hard assumption on lattice problem.

Jan 1, 20151 citation