• Journal of Digital Contents Society
• /
• v.12 no.2
• /
• pp.165-176
• /
• 2011

Recently, digital rights management (DRM) related researches are widely spreading with prosperity of IT industries. The DRM technology protects proprietor of copyright by preventing mischanneling and illegal copy. In this paper, we propose a new DRM model that has an enhanced and efficient protocol based on certificate using smart card. The proposed model overcomes weaknesses of WCDRM model and has following additional advantages: first, copy protection is enhanced by hiding user's specific information from attacker by storing the information within smart card; second, server load for contents encryption is reduced by making clear protocols among author, distributer, certificate authority, and users; third, offline user authentication is guaranteed by combining partial secret values in media players and smart card. Exposure of core information also is minimized by storing them in smart card. In addition, we show that the proposed system is more secure than WCDRM model by comparing various factors of anonymous attackers.

• The KIPS Transactions:PartC
• /
• v.14C no.3 s.113
• /
• pp.239-254
• /
• 2007

Ubiquitous computing supports environment to freely connect to network without restrictions of place and time. This environment enables easy access and sharing of information, but because of easy unauthorized accesses, specified security policy is needed. Especially, ubiquitous sensor network devices use limited power and are small in size, so, many restrictions on policies are bound to happen. This paper proposes double-key based light weight security protocol, independent to specific sensor OS, platform and routing protocol in ubiquitous sensor network. The proposed protocol supports safe symmetric key distribution, and allows security manager to change and manage security levels and keys. This had a strong merit by which small process can make large security measures. In the performance evaluation, the proposed light weight security protocol using double-key in ubiquitous sensor network allows relatively efficient low power security policy. It will be efficient to ubiquitous sensor network, such as smart of ace and smart home.

• Proceedings of the Korea Information Assurance Society Conference
• /
• 2004.05a
• /
• pp.111-117
• /
• 2004

In distributed-computing environments, there is a strong demand for the authentication and the access control of distributed-shared resources. I have presented role-based access control (RBAC) concept that is in the spotlight recently. RBAC model shows the standardized access control of complicated organization's resources. In RBAC, senior role has junior role's permission by virtue of role hierarchy. But, junior role cannot perform the permission, which is granted to the senior or other role groups. Inheritances of permissions in role hierarchies are static. In order to tackle this problem, I propose a dynamic role assignment, which classified into passive role assignment and active role assignment, and design dynamic role assignment protocol and implement role assignment server.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.6
• /
• pp.281-288
• /
• 2014

QR code (abbreviated from Quick Response Code) is code system that is strong in against to apply image processing techniques (skew, warp, blur, and rotate) as QR codes can store several hundred times the amount of information carried by ordinary bar codes. For this reason, QR code is used in various fields, e.g., air ticket (boarding control system), food(vegetables, meat etc.) tracking system, contact lenses management, prescription management, patient wrist band (patient management) etc. In this paper, we proposed reversible data hiding for binary images. A reversible data hiding algorithm, which can recover the original image without any distortion from the marked (stego) image after the hidden data have been extracted, because it is possible to use various kinds of purposes. QR code can be used to generate by anyone so it can be easily used for crime. In order to prevent crimes related QR code, reversible data hiding can confirm if QR code is counterfeit or not as including authentication information. In this paper, we proved proposed method as experiments.

• Journal of Korea Multimedia Society
• /
• v.6 no.5
• /
• pp.861-869
• /
• 2003

The rapid growth of multimedia network systems has caused overflowing illegal copies of digital contents. Among digital contents, watermarking technique can be used to protect ownership about the image. Copyright protection involves the authentication of image ownership and the identification of illegal copies of image. In this paper, a new digital watermarking technique using HVS and adaptive scale factor based on the wavelet transform is proposed to use the binary image watermark. The original image is decomposed by 3-level wavelet transform. It is embedded to baseband and high frequency band. The embedding in the baseband is considered robustness, the embedding in the high frequency band is concerned about HVS and invisibility. The watermarking of a visually recognizable binary image used the HVS and random permutation to protect the copyright. From the experimental results, we confirm that the proposed technique is strong to various attacks such as joint photographic experts ground(JPEG) compression, cropping, collusion, and inversion of lines.

• Journal of Korea Multimedia Society
• /
• v.9 no.10
• /
• pp.1304-1313
• /
• 2006

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. In this paper, we propose a secure and efficient protocol to transmit fingerprint images from a fingerprint sensor to a client by exploiting characteristics of fingerprint images. Because the fingerprint sensor is computationally limited, however, such encryption algorithm may not be applied to the full fingerprint images in real-time. To reduce the computational workload on the resource-constrained sensor, we apply the encryption algorithm to a specific bitplane of each pixel of the fingerprint image. We use the LSB as specific bitplane instead of MSB used to encrypt general multimedia contents because simple attacks can reveal the fingerprint ridge information even from the MSB-based encryption. Based on the experimental results, our proposed algorithm can reduce the execution time of the full encryption by a factor of six and guarantee both the integrity and the confidentiality without any leakage of the ridge information.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.2
• /
• pp.73-80
• /
• 2009

Security is critically important for ubiquitous sensor networks that are usually used for the military and serveillance in environments that are opened to attacks, such as, eavesdroping, replay attacks of abnormal messages, forgery of the messages to name a few. ZigBee has emerged as a strong contender for ubiquitous sensor networks. ZigBee is used for low data rate and low power wireless sensor network applications. To deploy ubiquitous sensor networks, the collected information requires protection from an adversary over the network in many cases. The security mechanism should be provided for collecting the information over the network. However, the ZigBee protocol has some security weaknesses. In this paper, these weaknesses are discussed and a method to improve security aspect of the ZigBee protocol is presented along with a comparison of the message complexity of the proposed security protocol with that of the current ZigBee protocol.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.40 no.4
• /
• pp.183-190
• /
• 2017

This paper proposes a dynamic magnetic field emulator (DMFE), which can electrically emulate information for the magnetic stripes of most widely used credit cards. Payment transactions with most common credit cards are performed by reading the card's information, encoded in magnetic stripes, using the reader head of a point-of-sale (POS) system. A stripe-type permanent magnet is attached to the back side of the credit card, and information for payments or value-added service is reorganized by exposing it to strong magnetic field. The process of data recording and retrieving as stated above has been pointed out as a major cause of illegal credit card use, because the information on the magnetic stripe is always exposed, and is thus vulnerable to forgery or alteration. A dynamic magnetic field emulator displays card information only when necessary by using the principle of solenoidal magnets. The DMFE proposed in this paper can prevent fraudulent use if it is operated with a device, like a smart phone, or a separate user-authentication procedure. In addition, because it is possible to display various information as needed, it can be utilized for a smart multi-card application, in which information for multiple cards is stored in one card, and can be selected and used as needed. This paper introduces the necessity of the DMFE and its manufacturing principles. As a result, this study will be helpful for making various application cases in payment, which is a core area of the Fintech (a newly-coined word of finance and technology) industry.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.18 no.2
• /
• pp.33-38
• /
• 2008

Biometric based authentication can provide strong security guarantee about the identity of users. However, security of biometric data is particularly important as compromise of the data will be permanent. Cancelable biometrics stores a non - invertible transformed version of the biometric data. Thus, even if the storage is compromised, the biometric data remains safe. Cancelable biometrics also provide a higher level of privacy by allowing many templates for the same biometric data and hence non-linkability of user's data stored in different databases. In this paper, we proposed the fast polynomial reconstruction algorithm for fuzzy fingerprint vault. The proposed method needs (k+1) real points to reconstruct the polynomial of degree (k-1). It enhances the speed, however, by $300{\sim}1500$ times according to the degree of polynomial compared with the exhaust search.

• 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.