• The KIPS Transactions:PartC
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• v.17C no.3
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• pp.233-242
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• 2010

In the recent years, power attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate results in the algorithm computations(encryption, decryption) are well-known. In case of SEED block cipher, it uses 32 bit arithmetic addition and S-box operations as non-linear operations. Therefore the masking type conversion operations, which require some operating time and memory, are required to satisfy the masking method of all non-linear operations. In this paper, we propose a new masked S-boxes that can minimize the number of the masking type conversion operation. Moreover we construct just one masked S-box table and propose a new formula that can compute the other masked S-box's output by using this S-box table. Therefore the memory requirements for masked S-boxes are reduced to half of the existing masking method's one.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.469-476
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• 2021

An electronic attack (EA) system is an essential weapon system for performing electronic warfare missions that contain signal tracking and jamming against multiple threats using electromagnetic waves, such as air defense radars, wireless command and communication networks, and guided missiles. The combat effectiveness can be maximized, and the survivability of militarily protecting combat power can be enhanced through EA mission operations, such as disabling the functions of multiple threats. The EA system can be used as a radio frequency jamming system to respond to drone attacks on the core infrastructure, such as airports, power plants, and communication broadcasting systems, in the civilian field. This study examined the criteria for classification according to the electronic attack missions of foreign EA systems based on an aviation platform. The foreign R&D trends by those criteria were investigated. Moreover, by analyzing the R&D trends of domestic EA systems and future battlefields in the domestic security environments, this paper proposes technological development plans of EA systems suitable for the future battlefield environments compared to the foreign R&D trends.

• Review of KIISC
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• v.30 no.5
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• pp.45-54
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• 2020

최근 주요정보통신기반시설 대상의 사이버 공격이 급격하게 증가하고 있다. 특히, 발전시설 주요정보통신기반시설에 사이버 공격 발생 시 전력 공급 중단으로 인하여 대규모 정전사고가 발생할 수 있다. 따라서, 발전시설 대상의 사이버보안 관리가 중요하며, 주기적인 사이버보안 평가가 필요하다. 미국 EPRI(Electric Power Research Institute)에서 발전시설 대상 사이버 보안조치 평가 방법론인 TAM(Technical Assessment Methodology)을 개발하였고, 최근 아랍에미리트(UAE, United Arab Emirates) 바라카(Barakah) 원자력발전소에서 사이버보안 평가를 위해 TAM을 활용하였다. 본 논문에서는 발전시설 사이버보안 평가 방법론인 TAM을 분석하고, 국내 발전시설 사이버보안 평가에 활용 방안을 제시하고자 한다.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.55-64
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• 2012

Until now, Side Channel Attack has been known to be effective to crack decrypt key such as smart cards, electronic passports and e-ID card based on Chip. Combination of Masking and shuffling methods have been proposed practical countermeasure. Newly, S.Tillich suggests biased-mask using template attack(TA) to attack AES with masking and shuffling. However, an additional assumption that is acquired template information previously for masking value is necessary in order to apply this method. Moreover, this method needs to know exact time position of the target masking value for higher probability of success. In this paper, we suggest new practical method called Biasing Power Analysis(BPA) to find a secret key of AES based on masking-shuffling method. In BPA, we don't use time position and template information from masking value. Actually, we do experimental works of BPA attack to 128bit secret key of AES based on masking-shuffling method performed MSP430 Chip and we succeed in finding whole secret key. The results of this study will be utilized for next-generation ID cards to verify physical safety.

• Journal of Digital Contents Society
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• v.17 no.6
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• pp.499-507
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• 2016

The era of IoT, which figures exchanging data from the internet between things is coming. Recently, former electric power energy policy paradigm, namely Supply side paradigm, is changing, because electric power energy consumption is rapidly increasing. As new paradigm for this limit, convergence of existing electric power grid and ICT(Information and Communication Technology) will accelerate intellectualization of electric power device, its operation system. This change brought opened electric power grid. Consequently, attacks to the national electric power grid are increasing. On this paper, we will analyze security threats of existing IoT, discuss security weakness on electric power industry IoT and suggest needed security requirements, security technology.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.3
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• pp.313-323
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• 2020

With the development of smart grid technologies, a user can use the secure and reliable power services in smart gird environments. However, the users are not secure against various potential attacks because the smart gird services are provided through the public channel. Therefore, a secure and lightweight authentication and key agreement scheme has become a very important security issue in smart grid in order to guarantee user's privacy. In 2019, Zhang et al. proposed a lightweight authentication scheme for smart gird communications. In this paper, we demonstrate that Zhang et al.'s scheme is vulnerable to impersonation and session key disclosure attacks, and then we propose a secure authentication and key agreement scheme for smart grid environments without tamper-resistant devices. Moreover, we perform the informal security and the BAN logic analysis to prove that our scheme is secure various attacks and provides secure mutual authentication, respectively. We also perform the performance analysis compared with related schemes. Therefore, the proposed scheme is efficiently applicable to practical smart gird environments.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.5
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• pp.1001-1011
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• 2017

A lattice-based cryptography is known as one of the post-quantum cryptographies. Ring-LWE problem is an algebraic variant of LWE, which operates over elements of polynomial rings instead of vectors. It is already known that post-quantum cryptography has side-channel analysis vulnerability. In 2016, Park et al. reported a SPA vulnerability of the public key cryptosystem, which is proposed by Roy et al., based on the ring-LWE problem. In 2015 and 2016, Reparaz et al. proposed DPA attack and countermeasures against Roy cryptosystem. In this paper, we show that the chosen ciphertext SPA attack is also possible for Lyubashevsky cryptosystem which does not use NTT. And then we propose a countermeasure against CCSPA(Chosen Ciphertext SPA) attack and we also show through experiment that our proposed countermeasure is secure.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.4
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• pp.801-816
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• 2021

This study analyzes the political and legislative progress that although basic acts to establish an integrated system of cybersecurity are steadily being proposed, they have not been passed as legislative deadlocks under the two major parties. It shall be analyzed through Korea's legislative system, including differences in contents and interests of the disposal act, the timing and cycle of election ect. The study analyzes why the basic cybersecurity law was previously scrapped and faced political gridlock situation by analyzing the differences in the contents and interests of the two major parties, and the timing and cycle of the proposed legislation.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.356-363
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• 2020

As a becoming era of Internet-of-Things, various devices are connected via wire or wirless networks. Although every day life is more convenient, security problems are also increasing such as privacy, information leak, denial of services. Since ECC, a kind of public key cryptosystem, has a smaller key size compared to RSA, it is widely used for environmentally constrained devices. The key of ECC in constrained devices can be exposed to power analysis attacks during scalar multiplication operation. In this paper, a key-randomization method is suggested for scalar multiplication on SECG parameters. It is against differential power analysis and has operational efficiency. In order to increase of operational efficiency, the proposed method uses the property 2^lP=∓cP where the constant c is small compared to the order n of SECG parameters and n=2^l±c. The number of operation for the Coron's key-randomization scalar multiplication algorithm is 21, but the number of operation for the proposed method in this paper is (3/2)l. It has efficiency about 25% compared to the Coron's method using full random numbers.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.3
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• pp.69-77
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• 2008

In the recent years, power attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate results in the algorithm computations(encryption, decryption, and key-schedule) are well-known. Applications of masking methods are able to vary in different block ciphers, therefore suitable masking methods about each ciphers have been researched. Existed methods of ARIA have many revisions of mask value. And because existed masking methods pay no regard for key schedule, secret information can be exposed. In the case of ARIA, this problem is more serious than different block ciphers. Therefore we proposes an efficient masking scheme of ARIA including the key-schedule. Our method reduces time-complexity of ARIA encryption, and solve table-size problem of the general ARIA masking scheme from 256*8 byte to 256*6 byte.