250 research outputs found
Best Effort and Practice Activation Codes
Activation Codes are used in many different digital services and known by
many different names including voucher, e-coupon and discount code. In this
paper we focus on a specific class of ACs that are short, human-readable,
fixed-length and represent value. Even though this class of codes is
extensively used there are no general guidelines for the design of Activation
Code schemes. We discuss different methods that are used in practice and
propose BEPAC, a new Activation Code scheme that provides both authenticity and
confidentiality. The small message space of activation codes introduces some
problems that are illustrated by an adaptive chosen-plaintext attack (CPA-2) on
a general 3-round Feis- tel network of size 2^(2n) . This attack recovers the
complete permutation from at most 2^(n+2) plaintext-ciphertext pairs. For this
reason, BEPAC is designed in such a way that authenticity and confidentiality
are in- dependent properties, i.e. loss of confidentiality does not imply loss
of authenticity.Comment: 15 pages, 3 figures, TrustBus 201
KLEIN: A New Family of Lightweight Block Ciphers
Resource-efficient cryptographic primitives become fundamental for realizing both security and efficiency in embedded systems like RFID tags and sensor nodes. Among those primitives, lightweight block cipher plays a major role as a building block for security protocols. In this paper, we describe a new family of lightweight block ciphers named KLEIN, which is designed for resource-constrained devices such as wireless sensors and RFID tags. Compared to the related proposals, KLEIN has advantage in the software performance on legacy sensor platforms, while in the same time its hardware implementation can also be compact
A Security Analysis of IoT Encryption: Side-channel Cube Attack on Simeck32/64
Simeck, a lightweight block cipher has been proposed to be one of the
encryption that can be employed in the Internet of Things (IoT) applications.
Therefore, this paper presents the security of the Simeck32/64 block cipher
against side-channel cube attack. We exhibit our attack against Simeck32/64
using the Hamming weight leakage assumption to extract linearly independent
equations in key bits. We have been able to find 32 linearly independent
equations in 32 key variables by only considering the second bit from the LSB
of the Hamming weight leakage of the internal state on the fourth round of the
cipher. This enables our attack to improve previous attacks on Simeck32/64
within side-channel attack model with better time and data complexity of 2^35
and 2^11.29 respectively.Comment: 12 pages, 6 figures, 4 tables, International Journal of Computer
Networks & Communication
A Survey of Lightweight Cryptosystems for Smart Home Devices
A Smart Home uses interconnected network technology to monitor the environment, control the various physical appliances, and communicate with each other in a close environment. A typical smart home is made up of a security system, intercommunication system, lighting system, and ventilation system. Data security schemes for smart homes are ineffective due to inefficiency cryptosystems, high energy consumption, and low exchange security. Traditional cryptosystems are less-applicable because of their large block size, large key size, and complex rounds. This paper conducts a review of smart homes, and adopts Ultra-Sooner Lightweight Cryptography to secure home door. It provides extensive background of cryptography, forms of cryptography as associated issues and strengths, current trends, smart home door system design, and future works suggestions. Specifically, there are prospects of utilizing XORed lightweight cryptosystem for developing encryption and decryption algorithms in smart home devices. The Substitution Permutation Network, and Feistel Network cryptographic primitives were most advanced forms of cipher operations with security guarantees. Therefore, better security, memory and energy efficiency can be obtained with lightweight ciphers in smart home devices when compared to existing solutions. In the subsequent studies, a blockchain-based lightweight cryptography can be the next springboard in attaining the most advanced security for smart home systems and their appliances.
 
Simulating Auxiliary Inputs, Revisited
For any pair of correlated random variables we can think of as a
randomized function of . Provided that is short, one can make this
function computationally efficient by allowing it to be only approximately
correct. In folklore this problem is known as \emph{simulating auxiliary
inputs}. This idea of simulating auxiliary information turns out to be a
powerful tool in computer science, finding applications in complexity theory,
cryptography, pseudorandomness and zero-knowledge. In this paper we revisit
this problem, achieving the following results:
\begin{enumerate}[(a)] We discuss and compare efficiency of known results,
finding the flaw in the best known bound claimed in the TCC'14 paper "How to
Fake Auxiliary Inputs". We present a novel boosting algorithm for constructing
the simulator. Our technique essentially fixes the flaw. This boosting proof is
of independent interest, as it shows how to handle "negative mass" issues when
constructing probability measures in descent algorithms. Our bounds are much
better than bounds known so far. To make the simulator
-indistinguishable we need the complexity in time/circuit size, which is better by a
factor compared to previous bounds. In particular, with our
technique we (finally) get meaningful provable security for the EUROCRYPT'09
leakage-resilient stream cipher instantiated with a standard 256-bit block
cipher, like .Comment: Some typos present in the previous version have been correcte
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