• Journal of KIISE
• /
• v.44 no.8
• /
• pp.860-869
• /
• 2017

Recently, due to the personal information security act, the encryption of personal information has attracted attention. However, if the conventional encryption scheme is used directly, the database schema must be changed because the conventional encryption scheme does not preserve the format of the data, which can yield a large cost. Therefore, the Format-Preserving Encryption(FPE) has emerged as an important technique that ensures the confidentiality of the data and maintains the database schema naturally. Accordingly, National Institute of Standards and Technology(NIST) recently published the FF1 and FF3 as standards for FPE, although problems have been found in the security of FF1 and FF3 against message recovery attacks. In this paper, we study and analyze FF1 and FF3 as the standards of FPE, as well as the message recovery attack on these schemes. We also study a secure FPE against message recovery attack and verify the efficiency by implementing standardized FF1 and FF3.

• Journal of Convergence Society for SMB
• /
• v.5 no.1
• /
• pp.25-30
• /
• 2015

The APT attacks are hackers created a variety of security threats will continue to attack applied to the network of a particular company or organization. It referred to as intelligent sustained attack. After securing your PC after a particular organization's internal staff access to internal server or database through the PC or remove and destroy the confidential information. The APT attack is so large, there are two zero-day attacks and rootkits. APT is a process of penetration attack, search, acquisition, and is divided into outlet Step 4. It was defined in two ways how you can respond to APT through the process. Technical descriptions were divided into ways to delay the attacker's malicious code attacks time and plan for attacks to be detected and removed through.

• Convergence Security Journal
• /
• v.19 no.2
• /
• pp.113-121
• /
• 2019

With the development of the Internet and Information Communication Technology, there has been an increase in the amount of Open Source Intelligence(OSINT). OSINT can be highly effective, if well refined and utilized. Recently, it has been assumed that almost 95% of all information comes from public sources and the utilization of open sources has sharply increased. The ISVG and START programs, for example, collect information about open sources related to terrorism or crime, effectively used to detect terrorists and prevent crime. The open source information related to the cyber attacks is, however, quite different from that in terrorism (or crime) in that it is difficult to clearly identify the attacker, the purpose of attack, and the range of damage. In addition, the data itself of cyber attacks is relatively unstructured. So, a totally new approach is required to establish and utilize an OSINT database for cyber attacks, which is proposed in this paper.

• Journal of Convergence Society for SMB
• /
• v.5 no.4
• /
• pp.37-42
• /
• 2015

Due to the advance of ICT, a variety of attacks have been developing and active. Recently, APT attacks using malicious codes have frequently occurred. Advanced Persistent Threat means that a hacker makes different security threats to attack a certain network of a company or an organization. Exploiting malicious codes or weaknesses, the hacker occupies an insider's PC of the company or the organization and accesses a server or a database through the PC to collect secrets or to destroy them. The paper suggested a countermeasure to cope with APT attacks through an APT attack process. It sought a countermeasure to delay the time to attack taken by the hacker and suggested the countermeasure able to detect and remove APT attacks.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.4B
• /
• pp.428-434
• /
• 2009

Many RFID authentication protocols have been proposed to build a secure ubiquitous environment. However, existing protocols do not respond recent attacks appropriately and they perform many hash operations to authenticate a large number of tags. In this paper, we propose a hash function-based secure authentication protocol for improving efficiency in RFID system. The proposed protocol is safe to passive attacks and active attacks, and requires only 2 hash operations in a tag and 3 hash operations in a database. Accordingly, the proposed protocol is very effective in RFID system environment which is composed to low-cost tags and a database handling many tags.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.4
• /
• pp.425-434
• /
• 2010

This study shows a limit to attacks that the prevention system, which is used as the mutual third aggressive packet path between open heterogeneous networks and applies prevention techniques according to the trace like IP tracking and attack methods, can prevent. Therefore, the study aims to learn information of constant attack routing protocol and of the path in network, the target of attack and build a database by encapsulating networks information routing protocol operates in order to prevent source attack paths. In addition, the study is conducted to divide network routing protocols developed from the process of dividing the various attack characters and prevent various attacks. This study is meaningful in that it analyzes attack path network and attacks of each routing protocol and secure exact mechanism for prevention by means of 3D-Puzzle, Path, and Cube of the integrated security system which is an implementation method of integrated information protection for access network defense.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.21 no.2
• /
• pp.13-25
• /
• 2011

Biometric-based authentication can provide strong security guarantee about the identity of users. However, security of biometric data is particularly important as the compromise of the data will be permanent. The fuzzy fingerprint vault system is one of the most popular solutions for protecting the fingerprint template stored in the database. Recently, however, this system is very susceptible to a correlation attack that finds the real minutiae using multiple fingerprint vaults enrolled for different applications. To solve this problem, we propose a robust fuzzy fingerprint vault system against the correlation attack. In this paper, we add chaff minutiae based on the relative information of minutiae such as direction, coordinate instead of adding randomly. Also, our proposed approach allow to add multiple chaff minutiae within tolerance box for enhanced security level. Experimental results show that the proposed approach can protect the correlation attack and achieve enhanced verification accuracy.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.4
• /
• pp.89-108
• /
• 2010

Recently many mutual authentication protocol for light-weight hash-based for RFID have been proposed. Most of them have assumed that communications between a backend server and reader are secure, and not considered threats for backend server and RFID reader impersonation. In the real world, however, attacks against database or reader are more effective rather than attacks against RFID tag, at least from attacker's perspective. In this paper, we assume that all communications are not secure to attackers except the physical attack, and considering realistic threats for designing a mutual authentication protocol based on hash function. And It supports a mutual authentication and can protect against the replay attack, impersonation attack, location tracking attack, and denial of service attack in the related work. We besides provide a secure and efficient RFID mutual authentication protocol which resists impersonation attacks on all of the entities and alow a backend server to search tag-related information efficiently. We conclude with analyzing the safety and efficiency among latest works.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.3
• /
• pp.493-500
• /
• 2015

Personal information exposed in the Internet is increasing by the public data opening and sharing, vitalization of SNS(Social Network Service) and growth of information shared between users. Exposed personal information in the Internet can infringe upon targeted users using linkage attack or background attack. To prevent these attack De-identification models were appeared a few years ago. The 'k-anonymity' has been introduced in the first place, and the '${\ell}$-diversity' and 't-closeness' have been followed up as solutions, and diverse algorithms have been being suggested for performance improvement nowadays. However, industry or public sectors actually needs a whole solution as a system for the de-identification process rather than performance of the de-identification algorithm. This paper explains a way of de-identification techique for 'k-anonymity', '${\ell}$-diversity', and 't-closeness' algorithm using QI(Quasi-Identifier) grouping method in the relational database.

• Journal of Aerospace System Engineering
• /
• v.15 no.5
• /
• pp.60-71
• /
• 2021

Propeller performance measurement system for commercial propeller was designed and applied to the wind tunnel test for 3 commercial propeller models with diameters of 30 inch. The thrust and torque of the propeller was directly measured by using 6-components balance installed on the rotating axis. The measurement system was validated by using wind tunnel balance calibration equipment. Propeller test stand including measurement and rotating system was validated by using QTP propeller. In the hovering condition, we compared the performance test results and the specifications of the commercial propeller provided by the manufacturer and confirmed that there are differences in the thrust and the torque. We measured the propeller performance with various wind speeds, propeller models and angles of attack and was summarized by thrust coefficients. We confirmed that the trend of the thrust coefficients was different in the low angle of attack and high angle of attack. An aerodynamics database that can be used for future aerodynamic design of an unmanned aerial vehicle was secured.