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A Cryptographic Processor Supporting ARIA/AES-based GCM Authenticated Encryption (ARIA/AES 기반 GCM 인증암호를 지원하는 암호 프로세서)

  • Sung, Byung-Yoon;Kim, Ki-Bbeum;Shin, Kyung-Wook
    • Journal of IKEEE
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    • v.22 no.2
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    • pp.233-241
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    • 2018
  • This paper describes a lightweight implementation of a cryptographic processor supporting GCM (Galois/Counter Mode) authenticated encryption (AE) that is based on the two block cipher algorithms of ARIA and AES. It also provides five modes of operation (ECB, CBC, OFB, CFB, CTR) for confidentiality as well as the key lengths of 128-bit and 256-bit. The ARIA and AES are integrated into a single hardware structure, which is based on their algorithm characteristics, and a $128{\times}12-b$ partially parallel GF (Galois field) multiplier is adopted to efficiently perform concurrent processing of CTR encryption and GHASH operation to achieve overall performance optimization. The hardware operation of the ARIA/AES-GCM AE processor was verified by FPGA implementation, and it occupied 60,800 gate equivalents (GEs) with a 180 nm CMOS cell library. The estimated throughput with the maximum clock frequency of 95 MHz are 1,105 Mbps and 810 Mbps in AES mode, 935 Mbps and 715 Mbps in ARIA mode, and 138~184 Mbps in GCM AE mode according to the key length.

Treatment effects of the Teuscher appliance in skeletal Class II division 1 malocclusion (골격성 II급 1류 부정교합에서 Teuscher 장치의 치료효과)

  • Mo, Sung-Seo;Sohn, Byung-Wha
    • The korean journal of orthodontics
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    • v.33 no.4 s.99
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    • pp.247-257
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    • 2003
  • Various methods have been used on patients with skeletal Class II division 1 malocclusion. The activator, Frankel appliance, headgear, Herbst appliance, and Twin-block appliance are some examples. The ideal treatment effect using these appliances would be to inhibit horizontal and vertical growth of the maxilla while promoting mandibular growth and obtaining optimum dentition. The Teuscher appliance has a simultaneous combined headgear effect with maxillary growth inhibition and an activator effect with mandibular growth promotion. The purpose of this study was to examine how well these effects were clinically obtained and the results are as follows. 1. The forward growth of the maxilla was effectively inhibited. 2. The downward-forward growth of the maxillary dentoalveolar complex was inhibited. 3. Growth promotion of the mandible was not observed. 4. The overjet, overbite, molar key were effectively improved. 5. The protruded upper lip and facial profile were unproved.

Impossible Differential Cryptanalysis of Reduced Round XTEA and TEA (XTEA와 TEA의 축소된 라운드에 대한 불능 차분 공격)

  • 문덕재;황경덕;이원일;이상진;임종인
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.12 no.4
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    • pp.77-85
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    • 2002
  • We present the impossible differential cryptanalysis of the block cipher XTEA[7] and TEA[6]. The core of the design principle of these block ciphers is an easy implementation and a simplicity. But this simplicity dose not offer a large diffusion property. Our impossible differential cryptanalysis of reduced-round versions of XTEA and TEA is based on this fact. We will show how to construct a 12-round impossible characteristic of XTEA. We can then derive 128-bit user key of the 14-round XTEA with $2^{62.5}$ chosen plaintexts and $2^{85}$ encryption times using the 12-round impossible characteristic. In addition, we will show how to construct a 10-round impossible characteristic or TEA. Then we can derive 128-bit user key or the 11-round TEA with $2^{52.5}$ chosen plaintexts and $2^{84}$ encryption times using the 10-round impossible characteristic.

Optimization of LEA Quantum Circuits to Apply Grover's Algorithm (그루버 알고리즘 적용을 위한 LEA 양자 회로 최적화)

  • Jang, Kyung Bae;Kim, Hyun Jun;Park, Jae Hoon;Song, Gyeung Ju;Seo, Hwa Jeong
    • KIPS Transactions on Computer and Communication Systems
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    • v.10 no.4
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    • pp.101-106
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    • 2021
  • Quantum algorithms and quantum computers can break the security of many of the ciphers we currently use. If Grover's algorithm is applied to a symmetric key cipher with n-bit security level, the security level can be lowered to (n/2)-bit. In order to apply Grover's algorithm, it is most important to optimize the target cipher as a quantum circuit because the symmetric key cipher must be implemented as a quantum circuit in the oracle function. Accordingly, researches on implementing AES(Advanced Encryption Standard) or lightweight block ciphers as quantum circuits have been actively conducted in recent years. In this paper, korean lightweight block cipher LEA was optimized and implemented as a quantum circuit. Compared to the previous LEA quantum circuit implementation, quantum gates were used more, but qubits were drastically reduced, and performance evaluation was performed for this tradeoff problem. Finally, we evaluated quantum resources for applying Grover's algorithm to the proposed LEA implementation.

Blockchain (A-PBFT) Based Authentication Method for Secure Lora Network (안전한 Lora 네트워크를 위한 블록체인(A-PBFT) 기반 인증 기법)

  • Kim, Sang-Geun
    • Journal of Industrial Convergence
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    • v.20 no.10
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    • pp.17-24
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    • 2022
  • Lora, a non-band network technology of the long-distance wireless standard LPWAN standard, uses ABP and OTTA methods and AES-128-based encryption algorithm (shared key) for internal terminal authentication and integrity verification. Lora's recent firmware tampering vulnerability and shared-key encryption algorithm structure make it difficult to defend against MITM attacks. In this study, the consensus algorithm(PBFT) is applied to the Lora network to enhance safety. It performs authentication and PBFT block chain creation by searching for node groups using the GPS module. As a result of the performance analysis, we established a new Lora trust network and proved that the latency of the consensus algorithm was improved. This study is a 4th industry convergence study and is intended to help improve the security technology of Lora devices in the future.

Differential Cryptanalysis on 15-Round IIoTBC Block Cipher Utilizing Cancellation of Differences (차분의 상쇄를 이용한 15-라운드 IIoTBC 블록암호에 대한 차분공격)

  • Wonwoo Song;Jaewon Seo;Yongjin Jeon;Jongsung Kim
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.34 no.4
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    • pp.569-575
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    • 2024
  • The 64-bit block cipher IIoTBC is an encryption algorithm designed for the security of industrial IoT devices and uses an 128-bit secret key. The IIoTBC's encryption algorithm varies depending on whether the MCU size used in IoT is 8-bit or 16-bit. This paper deals with a differential attack on IIoTBC when the MCU size is 8-bit. It attacks 15-round out of the entire 32-round using IIoTBC's 14-round differential characteristic. At this time, the number of required plaintexts and encryption are 257 and 2122.4, respectively. The differential characteristic presented in this paper has a longer round than the existing 13-round impossible differential characteristic, and the attack using this is the result of the first key recovery attack on IIoTBC.

Identification and Functional Analysis of LsMNPV Anti-apoptosis Genes

  • Kim, Yu-Sin;Xiao, Hua-Zhong;Du, En-Qi;Cai, Guo-Shuai;Lu, Song-Ya;Qi, Yi-Peng
    • BMB Reports
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    • v.40 no.4
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    • pp.571-576
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    • 2007
  • Three anti-apoptosis genes, Ls-iap2, iap3 and p49 were found in Leucania separata multiple nuclear polyhedrovirus. Amino acid sequence homology of Ls-IAP2 and Ls-IAP3 with Op-IAP2 and Op-IAP3 from Orgyia pseddotsugata MNPV were 20% and 42%, while that of Ls-P49 is 28% with Sl-P49 from Spodoptera littorolis MNPV. Ls-IAP2 contains one baculoviral IAP repeat (BIR) domain followed by a RING domain, while Ls-IAP3 contains two BIRs and a RING. Ls-P49 contains a reactive site loop, predicted cleavage site (KKLD$^{74}{\downarrow}$G) that is different from Sl-P49 (TVID$^{94}{\downarrow}$G). Expressed Ls-iap3 or Ls-p49 under presence of actinomycin D in SF9 cells, DNA ladder assayrevealed that Ls- IAP3 or Ls-P49 could block the apoptosis of SF9 cells induced by actinomycin D. Replication of p35 deficient-mutant Autographa californica MNPV in SF9 cells was also rescued when Ls-iap3 or Ls-p49 was expressed transiently. No anti-apoptotic activity was observed for Ls-IAP2. The results showed that both of Ls-IAP3 and Ls-P49 were functional apoptotic suppressors in SF9 cells.

Downregulation of Cdk1 and CyclinB1 Expression Contributes to Oridonin-induced Cell Cycle Arrest at G2/M Phase and Growth Inhibition in SGC-7901 Gastric Cancer Cells

  • Gao, Shi-Yong;Li, Jun;Qu, Xiao-Ying;Zhu, Nan;Ji, Yu-Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.6437-6441
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    • 2014
  • Background: Oridonin isolated from Rabdosia rubescens, a plant used to treat cancer in Chinese folk medicine, is one of the most important antitumor active ingredients. Previous studies have shown that oridonin has antitumor activities in vivo and in vitro, but little is known about cell cycle effects of oridonin in gastric cancer. Materials and Methods: MTT assay was adopted to detect the proliferation inhibition of SGC-7901 cells, the cell cycle was assessed by flow cytometry and protein expression by Western blotting. Results: Oridonin could inhibit SGC-7901 cell proliferation, the $IC_{50}$ being $15.6{\mu}M$, and blocked SGC-7901 cell cycling in the $G_2/M$ phase. The agent also decreased the protein expression of cyclinB1 and CDK1. Conclusions: Oridonin may inhibit SGC-7901 growth and block the cells in the $G_2/M$ phase by decreasing Cdk1 and cyclinB1 proteins.

Tumour-Derived Reg3A Educates Dendritic Cells to Promote Pancreatic Cancer Progression

  • Guo, Jie;Liao, Mengfan;Hu, Xianmin;Wang, Jun
    • Molecules and Cells
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    • v.44 no.9
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    • pp.647-657
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    • 2021
  • As a pancreatic inflammatory marker, regenerating islet-derived protein 3A (Reg3A) plays a key role in inflammation-associated pancreatic carcinogenesis by promoting cell proliferation, inhibiting apoptosis, and regulating cancer cell migration and invasion. This study aimed to reveal a novel immuno-regulatory mechanism by which Reg3A modulates tumour-promoting responses during pancreatic cancer (PC) progression. In an in vitro Transwell system that allowed the direct co-culture of human peripheral blood-derived dendritic cells (DCs) and Reg3A-overexpressing/ silenced human PC cells, PC cell-derived Reg3A was found to downregulate CD80, CD83 and CD86 expression on educated DCs, increase DC endocytic function, inhibit DC-induced T lymphocyte proliferation, reduce IL-12p70 production, and enhance IL-23 production by DCs. The positive effect of tumour-derived Reg3A-educated human DCs on PC progression was demonstrated in vivo by intraperitoneally transferring them into PC-implanted severe combined immunodeficiency (SCID) mice reconstituted with human T cells. A Reg3A-JAK2/STAT3 positive feedback loop was identified in DCs educated with Reg3A. In conclusion, as a tumour-derived factor, Reg3A acted to block the differentiation and maturation of the most important antigen-presenting cells, DCs, causing them to limit their potential anti-tumour responses, thus facilitating PC escape and progression.

An Efficient Post-Quantum Signature Scheme Based on Multivariate-Quadratic Equations with Shorter Secret Keys (양자컴퓨터에 안전한 짧은 비밀키를 갖는 효율적인 다변수 이차식 기반 전자서명 알고리즘 설계)

  • Kyung-Ah Shim
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.33 no.2
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    • pp.211-222
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    • 2023
  • Multivariate quadratic equations (MQ)-based public-key cryptographic algorithms are one of promising post-quantumreplacements for currently used public-key cryptography. After selecting to NIST Post-Quantum Cryptography StandardizationRound 3 as one of digital signature finalists, Rainbow was cryptanalyzed by advanced algebraic attacks due to its multiple layered structure. The researches on MQ-based schemes are focusing on UOV with a single layer. In this paper, we propose a new MQ-signature scheme based on UOV using the combinations of the special structure of linear equations, spare polynomials and random polynomials to reduce the secret key size. Our scheme uses the block inversion method using half-sized blockmatrices to improve signing performance. We then provide security analysis, suggest secure parameters at three security levels and investigate their key sizes and signature sizes. Our scheme has the shortest signature length among post-quantumsignature schemes based on other hard problems and its secret key size is reduced by up to 97% compared to UOV.