Basing on Learning with errors over rings (RLWE) assumption, we provide a new multi-bit somewhat homomorphic encryption scheme. We introduce canonical embedding to transform a ring element into a vector, such that polynomial multiplication can be performed in  ~ (nlog n) scalar operations, and ciphertext size is reduced at the same time. The CPA security of this scheme can be reduced into RLWE...

Abstract Quantum computers promise not only to outperform classical machines for certain important tasks, but also preserve privacy of computation. For example, the blind quantum computing protocol enables secure delegated computation, where a client can protect their data and algorithms from server assigned run However, this security comes with practical limitation that must communicate after ...

In STOC ’08, Peikert and Waters introduced a powerful new primitive called Lossy Trapdoor Functions (LTDFs). Since their introduction, lossy trapdoor functions have found many uses in cryptography. In the work of Peikert and Waters, lossy trapdoor functions were used to give an efficient construction of a chosen-ciphertext secure (IND-CCA2) cryptosystem. Lossy trapdoor functions were then shown...

We try to propose two fully homomorphic encryption (FHE) schemes, one for symmetric (aka. secret-key) settings and another under asymmetric (aka. public-key) scenario. The presented schemes are noiseless in the sense that there is no “noise” factor contained in the ciphertexts. Or equivalently, before performing fully homomorphic computations, our schemes do not incorporate any noise-control pr...

Encryption schemes that support computation on encrypted data are useful in constructing efficient and intuitively simple cryptographic protocols. However, the approach was previously limited to stand-alone and/or honest-but-curious security. In this work, we apply recent results on “non-malleable homomorphic encryption” to construct new protocols with Universally Composable security against ac...

We show that homomorphic evaluation of any non-trivial functionality of sufficiently many inputs with respect to any CPA secure homomorphic encryption scheme cannot be implemented by circuits of polynomial size and constant depth, i.e., in the class AC. In contrast, we observe that there exist ordinary public-key encryption schemes of quasipolynomial security in AC assuming noisy parities are e...

Inspired by rodents’ free navigation through a specific space, RatSLAM mimics the function of rat hippocampus to establish an environmental model within which agent localizes itself. However, suffers from deficiencies erroneous loop-closure detection, low reliability on experience map, and weak adaptability changes, such as lighting variation. To enhance adaptability, this paper proposes improv...

Nowadays, the internet of things (IoT) is used to generate data in several application domains. A logistic regression, which a standard machine learning algorithm with wide range, built on such data. Nevertheless, building powerful and effective regression model requires large amounts Thus, collaboration between multiple IoT participants has often been go-to approach. However, privacy concerns ...

The efficiency of fully homomorphic encryption is a big question at present. To improve efficiency of fully homomorphic encryption, we use the technique of packed ciphertext to construct a multi-bit fully homomorphic encryption based on Learning with Errors problem. Our scheme has a short public key. Since our fully homomorphic encryption scheme builds on the basic encryption scheme that choose...