• Journal of information and communication convergence engineering
• /
• v.9 no.6
• /
• pp.683-688
• /
• 2011

The wireless sensor network (WSN) is well known for an enabling technology for the ubiquitous environment such as real-time surveillance system, habitat monitoring, home automation and healthcare applications. However, the WSN featuring wireless communication through air, a resource constraints device and irregular network topology, is threatened by malicious nodes such as eavesdropping, forgery, illegal modification or denial of services. For this reason, security in the WSN is key factor for utilizing the sensor network into the commercial way. There is a series of symmetric cryptography proposed by laboratory or industry for a long time. Among of them, recently proposed HUMMINGBIRD algorithm, motivated by the design of the well-known Enigma machine, is much more suitable to resource constrained devices, including smart card, sensor node and RFID tags in terms of computational complexity and block size. It also provides resistance to the most common attacks such as linear and differential cryptanalysis. In this paper, we implements ultra-lightweight cryptography, HUMMINGBIRD algorithm into the resource constrained device, sensor node as a perfectly customized design of sensor node.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.7
• /
• pp.1495-1500
• /
• 2011

Dynamic cipher has the property that the key-size, the number of round, and the plain text-size are scalable simultaneously. In this paper we propose the block cipher algorithm which is symmetrical in the dynamic network. We present the method for designing secure Dynamic cipher against meet-in-the-middle attack and linear crytanalysis. Also, we show that the differential cryptanalysis to Dynamic cipher is hard.

• Journal of Korea Multimedia Society
• /
• v.11 no.6
• /
• pp.852-859
• /
• 2008

In this paper, we propose a dynamic keyed block encryption algorithm. Most existing encryption algorithms are designed such that the key is not changed. Therefore, they have a disadvantage that plaintext could be easily exposed by differential and linear cryptanalysis. In the proposed algorithm, several key generators are designed, and a key generator is attached to the encryption procedure. After performing the encryption procedure, ciphertext and the initial key generating values are transferred to the receiver's key generator for decryption. Through simulation, the proposed algorithm is verified to satisfy the requirements of real-time processing and proved to have a high strength. It can be applied to practical use.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.3
• /
• pp.349-356
• /
• 2020

GIFT is a PRESENT-like cryptographic algorithm proposed in CHES 2017 and used S-box that can be implemented through a bit-slice technique[1]. Since bit-permutation is used as a linear layer, it can be efficiently implemented in hardware, but bit-slice implementation in software requires a specific conversion process, which is costly. In this paper, we propose a new bit-permutation that enables efficient bit-slice implementation and GIFT-64-variant using it. GIFT-64-variant has better safety than the existing GIFT in terms of differential and linear cryptanalysis.

• Journal of the Korea Computer Industry Society
• /
• v.10 no.4
• /
• pp.167-176
• /
• 2009

In this paper, we propose an improved SHACAL-1 of the same encryption and decryption with a simple symmetric layer. SHACAL-1 has 4 rounds, and each round has 20 steps. Decryption is becoming inverse function of encryption, In this paper, we proposed SHACAL-1 are composed of the first half, symmetry layer and the last half. The first half with SHACAL-1 encryption algorithm 1 round does with 10 steps and composes of 4 round. The last half identically with SHACAL-1 decryption algorithm, has a structure. On the center inserts a symmetry layer, encryption and decryption algorithm identically, composes. In the experiments, the proposed SHACAL-1 algorithm showed similar execution time to that of the SHACAL-1. Thanks to the symmetric layer, the proposed algorithm makes it difficult for the attacks which take advantages of high probability path such as the linear cryptanalysis, differential cryptanalysis. The proposed algorithm can be applicable to the other block cipher algorithms which have different encryption and decryption and useful for designing a new block cipher algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.6
• /
• pp.2148-2167
• /
• 2021

The proliferation of the Internet of Things (IoT) technologies and applications, especially the rapid rise in the use of mobile devices, from individuals to organizations, has led to the fundamental role of secure wireless networks in all aspects of services that presented with many opportunities and challenges. To ensure the CIA (confidentiality, integrity and accessibility) security model of the networks security and high efficiency of performance results in various resource-constrained applications and environments of the IoT platform, DDO-(data-driven operation) based constructions have been introduced as a primitive design that meet the demand of high speed encryption systems. Among of them, the TMN-family ciphers which were proposed by Tuan P.M., Do Thi B., etc., in 2016, are entirely suitable approaches for various communication applications of wireless mobile networks (WMNs) and advanced wireless sensor networks (WSNs) with high flexibility, applicability and mobility shown in two different algorithm selections, TMN64 and TMN128. The two ciphers provide strong security against known cryptanalysis, such as linear attacks and differential attacks. In this study, we demonstrate new probability results on the security of the two TMN construction versions - TMN64 and TMN128, by proposing efficient related-key recovery attacks. The high probability characteristics (DCs) are constructed under the related-key differential properties on a full number of function rounds of TMN64 and TMN128, as 10-rounds and 12-rounds, respectively. Hence, the amplified boomerang attacks can be applied to break these two ciphers with appropriate complexity of data and time consumptions. The work is expected to be extended and improved with the latest BCT technique for better cryptanalytic results in further research.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.1
• /
• pp.123-136
• /
• 2004

In this paper, complexity and regularity of polynomial multiplication over $GF({2^n})$ are defined by using Hamming weight of rows and columns of the matrix ever GF(2) which represents polynomial multiplication. It is shown experimentally that in order to construct the block cipher robust against differential cryptanalysis, polynomial multiplication of substitution layer and the permutation layer should have high complexity and high regularity. With result of the experiment, a way of constituting S box and G function is suggested in the block cipher whose structure is similar to SEED, which is KOREA standard of 128-bit block cipher. S box can be formed with a nonlinear function and an affine transform. Nonlinear function must be strong with differential attack and linear attack, and it consists of an inverse number over $GF({2^8})$ which has neither a fixed pout, whose input and output are the same except 0 and 1, nor an opposite fixed number, whose output is one`s complement of the input. Affine transform can be constituted so that the input/output correlation can be the lowest and there can be no fixed point or opposite fixed point. G function undergoes linear transform with 4 S-box outputs using the matrix of 4${\times}$4 over $GF({2^8})$. The components in the matrix of linear transformation have high complexity and high regularity. Furthermore, G function can be constituted so that MDS(Maximum Distance Separable) code can be formed, SAC(Strict Avalanche Criterion) can be met, and there can be no weak input where a fixed point an opposite fixed point, and output can be two`s complement of input. The primitive polynomials of nonlinear function affine transform and linear transformation are different each other. The S box and G function suggested in this paper can be used as a constituent of the block cipher with high security, in that they are strong with differential attack and linear attack with no weak input and they are excellent at diffusion.