• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.7
• /
• pp.1493-1500
• /
• 2004

Today's Commercial security server system which provide secrecy, integrity and availability may still be vulnerable to denial-of-service attacks. Authentication system whith use a public key cryptography and process RSA encryption is relatively slow and the slowness has become a major security threat specifically in service flooding attacks caused by authentication requests. The service flooding attacks render the server incapable of providing its service to legitimitive clients. Therefore the importance of implementing systems that prevent denial of service attacks and provide service to legitimitive users cannot be overemphasized. In this paper, we propose a puzzle protocol which applies to authentication model. our gradually strengthening authentication model improves the availability and continuity of services and prevent denial of service attacks and we implement flooding of service tolerance system to verify the efficiency of our model. This system is expected to be ensure in the promotion of reliability.

• Proceedings of the KAIS Fall Conference
• /
• 2007.05a
• /
• pp.199-202
• /
• 2007

In this paper, I suggest that as follow. First, it is the algorithm to transmit the encryption key which use ${\ast}$ N Puzzle method more safe than the existing One-path XOR method. Second, it does provide the high quality of security than the existing system because it does not save the generated puzzle to the setter side. Third, it does support the client decryption system which can decrypt the puzzle with OPT in decryption with client side. Fourth, it does adopt more of the safe tansmission method with the compound of ${\ast}$ N Puzzle method and OPT.

• Korean Journal of Cognitive Science
• /
• v.6 no.1
• /
• pp.31-46
• /
• 1995

According to the Fregean theory of meaning based on the distinction between sense and reference,the cognitive significance of coreferential names may be distinct or The so-called direct reference theorists. however,claim that unamhbiguous,coreferential names.which have the same denotation from context to context, must have the same cognitive significance.Thereby,Fregean senses,counted as intermediate entities that determine the denotation of a term,are altogether rejected.Once Fregean senses are rejected.however,it is hard to explain why the substitytivity of coreferential names fails in the contexts of propositional attitudes.Thus,the puzzles of propositional attitudes have been the stumbling block for direct reference theorists. Recently, Zalta claimed that by small amendation it is possible to reconcile the conflicting views of Fregeans and the direct reference theorists without losing their important insights.Indeed, he claimed that his suggestion admirably solves the propositional puzzles.In this article,we shall critically examine his eclectic solution only to highlight some of the more basic issues.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.4
• /
• pp.936-944
• /
• 2008

DRM system is a technology that protects and manages copyright holder's privilege by using a copyright protection technology. This paper contributes to improvement of the secret key transmission and encryption/decryption processing time base on DRM system. In this paper, we will suggest that as follow: First, we will propose the algorithm to transmit the encryption key which use Multidimensional Method more safe than the existing One-path XOR method. Second, we will provide the high quality algorithm of security than the existing system because the Multidimensional which generated from the algorithm does not saved to the server side. Third, we will support the client decryption system which can decrypt the Multidimensional with OPT in decryption with client side. Fourth, we will adopt the more safr method of transmission with the compound of Multidimensional Method and OPT.