• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1305-1314
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• 2011

Initial entry section has vulnerability which exposes plain text parameter in Mobile WIMAX environment which is the 4th generation technology. Each node message need to be encrypted to prevent the third party attack or message leakage. In this paper, we propose Mobile WIMAX initial entry section encryption using Elliptic Curve Cryptosystem. We have compared proposed model with existing model using OPNET simulator tool. He delay rate has increased little bit in initial entry section than before after the comparison, but it has shown more effective in average delay and throughput than encryption applied other existing model.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.1
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• pp.19-32
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• 2013

As cyber stock trading grows rapidly, stock trading using Home Trading System have been brisk recently. Home Trading System is a heavy-weight in the stock market, and the system has shown 75% and 40% market shares for KOSPI and KOSDAQ, respectively. However, since Home Trading System focuses on the convenience and the availability, it has some security problems. In this paper, we found that the authentication information in memory remains during the stock trading and we proposed its countermeasure through two-channel authentication using a mobile device such as a cell phone.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.6
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• pp.63-68
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• 2009

In the whole information technology area, the protection of information from hacking or tapping becomes a very serious issue. Therefore, the more effective, convenient and secure methods are required to make the safe operation. Encryption algorithms are known to be computationally intensive. They consume a significant amount of computing resources such as CPU time and memory. In this paper we propose the scalable encryption scheme with four criteria, the compression of plaintext, variable size of block, selectable round and software optimization. We have tested our scheme by c++. Experimental results show that our scheme achieves the faster execution speed of encryption/decryption.

• Journal of the Korea Society of Computer and Information
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• v.8 no.4
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• pp.104-110
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• 2003

In this paper, we proposed hybrid cryptosystem of Diffie-Hellman base in Elliptic Curve, and explained for specific protocol design. The proposed system is efficient hybrid cryptosystems system that offer implicit key authentication about sender and receiver unlike existing hybrid system. This system increased safety generating session key using pseudo-random number generator by cryptographic. Because the system is hybrid system, it is more efficient in calculation amount aspect supplementing merit and fault of public key system and secret key system. Also, the system can not get right plaintext except receiver even if sender's secret key is revealed and impersonation attack is impossible. And the system offers security on known keys without influencing in safety of other session's cryptogram even if session key is exposed. And the system is provided safety about mutual entity authentication and replay attack.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.1
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• pp.65-68
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• 2006

Contact urticaria describes a wheal and falre response elicitied within 30-60 minutes after cutaneous exposure to certain agents. Contact urticaria encompasses a number of different clinical manifestations and the symptoms which can vary from the mildest forms of burning, stinging and itching sensation to life-threatening anaphylaxis referred to as contact urticaria syndrome. Cefotiam is one of the most popular second generation cephem antibiotic used in korea. Since 1975, contact urticaria due to cephalosporins has been reported, and also, in japan, this reported from about last 15 years. Recently we experienced three nurses working at the general wards with showing contact urticaria and anaphylaxis after occupational exposure to cefotiam antibiotics.

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.977-983
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• 2009

Recently, several DDP, DDO and COS-based block ciphers have been proposed for hardware implementations with low cost. However, most of them are vulnerable to related-keyt attacks. A 12-round block cipher SCOS-3 is desinged to eliminate the weakness of DDP, DDO and COS-based block ciphers. In this paper, we propose a related-key differential attack on an 11-round reduced SCOS-3. The attack on an 11-round reduced SCOS-3 requires $2^{58}$ related-key chosen plaintexts and $2^{117.54}$ 11-round reduced SCOS-3 encryptions. This work is the first known attack on SCOS-3. Therefore, SCOS-3 is still vulnerable to related-key attacks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.11C
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• pp.1090-1096
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• 2002

The HTTP does not support continuity for browser-server interaction between successive visits or a user due to a stateless feature. Cookies were invented to maintain continuity and state on the Web. Because cookies are transmitted in plain and contain text-character strings encoding relevant information about the user, the attacker can easily copy and modify them for his undue profit. In this paper, we design a secure cookies scheme based on X.509 public key certificate for solving these security weakness of typical web cookies. Our secure cookies scheme provides not only mutual authentication between client and server but also confidentiality and integrity of user information. Additionally, we implement our secure cookies scheme and compare it to the performance with SSL(Secure Socket Layer) protocol that is widely used for security of HTTP environment.

• Smart Media Journal
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• v.4 no.4
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• pp.33-38
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• 2015

Cloud storage server do not detect duplication of conventionally encrypted data. To solve this problem, Convergent Encryption has been proposed. Recently, various client-side deduplication technology has been proposed. However, this propositions still cannot solve the security problem. In this paper, we suggest a secure source-based deduplication technology, which encrypt data to ensure the confidentiality of sensitive data and apply proofs of ownership protocol to control access to the data, from curious cloud server and malicious user.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.175-181
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• 2016

Cloud storage servers do not detect duplication of conventionally encrypted data. To solve this problem, convergent encryption has been proposed. Recently, various client-side deduplication technology has been proposed. However, this propositions still cannot solve the security problem. In this paper, we suggest a secure source-based deduplication technology, which encrypt data to ensure the confidentiality of sensitive data and apply proofs of ownership protocol to control access to the data, from curious cloud server and malicious user.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.702-705
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• 2017

최근 들어 개인정보 보호의 중요성에 대한 인식이 높아지고 있다. 개인정보 위협 요소 증가 및 유출 사고 증가 등으로 개인정보 보호 필요성이 높아지고 있으며, 개인정보보호법 발효 및 시행에 따른 기술적 보호 마련을 위하여 외국계 카드 발행사에서 지속적으로 PCI DSS(Payment Card Industry Data Security Standard)의 준수를 요청하고 있다. 카드 소유자의 데이터를 전송, 처리, 저장하는 환경에 대한 인증으로 적격업체 선정의 자격을 주기도 한다. 이러한 보안성 심의 기준이 강화되고 있으나 DB 암호화 제품인 TDE(Transparent Data Encryption) 방식의 암호화 방법은 암호화 기능 이외에 접근제어, 키 기밀성 보장을 위한 옵션의 추가 도입 검토가 필요하며, 서비스를 위해서 DB 전용 메모리 영역(SGA)의 Buffer Cache에 평문(Plain Text)으로 복호화한 후 로드하여 사용하므로 예상치 못한 또 다른 심각한 데이터 유출의 위험이 있다. 본 논문에서는 개인정보 암호화 방법을 연구하고 구현과정에서 발생한 문제에 대한 해결 과정을 설명하였다.