• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.4
• /
• pp.841-849
• /
• 2012

Cloud computing that provides IT service and computer resource based on internet is now getting attention. However, the encrypted data can be exposed because it is saved in cloud server, even though it is saved as an encrypted data. In this paper, user certification protocol is proposed to prevent from illegally using of secret data by others while user who locates different physical position is providing secret data safely. The proposed protocol uses one way hash function and XOR calculation to get user's certification information which is in server when any user approaches to particular server remotely. Also it solves user security problem of cloud.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.6
• /
• pp.159-166
• /
• 2013

Recently, because the interest and needs in privacy protection are growing, smartcard-based remote user authentication schemes have been actively studied to provide the user anonymity. In 2008, Kim et al. first proposed an authentication scheme in order to ensure the user anonymity against both external attackers and the remote server and track malicious users with the help of a trusted trace sever. However, in 2010, Lee et al. showed that Kim et al.'s scheme cannot provide the user anonymity against remote server, which is because the server can trace users without any help of the trace server, and then proposed a improved scheme. On the other hand, in 2010, Horng et al. proposed an authentication scheme with non-tamper resistant smart cards, in which the non-tamper resistant smart card means that an attacker may find out secret information stored in the smart card through special data analysis techniques such as monitoring power consumption, to be secure against a variety of attacks and to provide the user anonymity against external attackers. In this paper, we will propose a remote user authentication scheme with non-tamper resistant smart cards not only to ensure the user anonymity against both external attackers and the remote server but also to track malicious users with only the help of a trusted trace sever.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
• /
• 2003.12a
• /
• pp.597-601
• /
• 2003

무선랜 환경에서 무선랜 단말이 AP(Access Point)사이를 로밍(Roaming)할 때 무선랜단말의 안전한 핸드오프를 위한 프로토콜로서 IAPP(InterAccess Point Protocol)가 있고 관련된 IEEE표준으로 802.11f가 있다. 무선랜단말의 안전한 핸드오프를 위해서는 IAPP를 통하여 기존에 접속되었던 AP에서 새로운 AP에게 무선랜단말의 인증 또는 과금관련 정보를 안전하게 전달하는 것이 필요하다. IEEE 802.11f에서는 무선랜단말의 핸드오프를 지원하는 액세스포인트를 인증하고 AP사이의 안전한 통신을 위한 정보를 제공하는 IAPP서버로 라디우스(RADIUS) 서버를 권고한다. 본 논문에서는 라디우스 서버의 한계를 극복하고 보다 확장성과 신뢰성이 뛰어난 서버를 위해 Diameter를 사용한 IAPP 서버의 구조와 동작에 대해서 설 명 한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.9
• /
• pp.2197-2204
• /
• 2015

In recent times, the high-tech society has become the most important issue by IT technology and publication network. Today such flows have also been the case in the e-book field. Today's electronic publication is changing day by day. But there are some problems according to the prevalence of e-book. E-book is similar to p-book(paper-book). There is a limit to have perfect feeling of a texture of p-book. In order to purchase an e-book, people use online. People having malicious intent could copy and distribute it illegally. It leads to cyber abuses. This paper aims at the copyright protection of e-book ePub writers. The proposed e-book copyright protection system is designed using e-book production Sigil environment and C program environment. This system uses client-server communication through e-book ePub as authentication information. It discerns whether to permit or not for a client to read the e-book using authentication information. Authentication information includes ID, password, IP address, limited time of authentication information, GUID(Globally Unique Identifier). If authentication information about e-book meets requirements, people can use it. But if not, it blocks people's approach by quitting program.

• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.83-91
• /
• 2006

In this paper, we improved a cryptography system model based on the secure initial authentication public key with PKINIT of authentication and key recovery protocol. It is applied to all fields of cryptography system using certificate. This study presents two mechanisms to authenticate between member users. The first mechanism is initial authentication and distribution of session key by public key cryptography based on certificate between entity and server, and the second mechanism is a key recovery support protocol considering loss of session key in the secure communication between application servers.

• 한국IT서비스학회:학술대회논문집
• /
• 2008.11a
• /
• pp.461-464
• /
• 2008

본 논문에서는 SIP 기반의 VoIP 서비스 환경에서 보안성 확보를 위해 속성인증서를 사용한 사용자 인증 시스템을 설계하였다. Redirect Server와 인증 서버를 각 Proxy Server 사이에 두어 인증서의 발급 및 검증, 사용자의 등록 및 관리 기능을 수행한다. 기존에 인증 시스템은 사용자 인증서가 외부에 노출이 되면 심각한 보안상의 문제가 발생할 수 있지만 속성인증서를 사용하면 외부에 노출에도 강력한 보안을 적용할 수 있다. 이에 본 논문에서는 속성인증서를 인증 서버가 발급과 검증을 하므로 안전한 통신 시스템을 구현할 수 있으며, 서비스 사용자를 Redirect Server에 등록 하게 함으로써 불법사용자의 접근을 제한하고, 정상적인 사용자를 인증하여 사용자의 정보보안 및 올바른 서비스의 제공이나 서비스 이용 요금의 과금시 유용하게 사용될 수 있다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2012.07a
• /
• pp.343-344
• /
• 2012

국제해사기구(IMO)에서 진행하는 "e-Navigation" 프로젝트의 구성요소인 해상교통관제시스템(VTS)을 정의하고, VTS 시스템간 정보교류를 위한 기술로 IVEF(Inter-system VTS Exchange Format)를 소개한다. 현재까지 국제항로표지협회(IALA)에서 개발한 IVEF에는 접속자에 대한 신뢰도 높은 인증 기술이 포함되지 않는다. 하지만 해상교통정보는 국가적으로 보안수위가 높은 정보이므로 정보 요청 자에 대한 신뢰 높은 인증이 절대적으로 필요한 부분이다. 따라서 본 논문에서는 메인 인증 서버와 IVEF를 이용하여 VTS 시스템간의 신뢰도를 높일 수 있는 인증 시스템을 제안한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2005.07a
• /
• pp.217-219
• /
• 2005

본 논문에서는 사이트 인증을 위해 효율적으로 토큰을 업데이트하여 등록된 사용자만을 대상으로 인증하는 것을 목적으로 하고 있다. 일반적인 OTP(one-time password)와 스마트카드를 이용한 인증은 다양한 공격에서 서버와 클라이언트를 보호하는데 사용이 되고 있으며, KIC(key information center)를 통해 서버와 클라이언트를 상호 인증을 한다. 제안하고 있는 기법에서 KIC를 거치지 않고 대체 사용이 가능한 컴퓨터 안에 있는 랜 카드의 고유한 값인 맥(media access control) 주소와 난수를 사용하여 토큰을 업데이트하는 방법은 사이트 인증에 매우 효율적인 알고리즘이다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.3C
• /
• pp.133-139
• /
• 2011

Nowadays, it is considered as an important task to protect digital contents from illegal use and reproduction. In many cases, there are secure servers to authenticate the allowed users and the user authentication process is performed by communication between the servers and users. However, if the number of users and contents are increased, the servers should treat a large amount of authentication loads and the authentication cost will be considerably increased. Moreover, this scheme is not adequate for some players in which only a limited function of communication is deployed. In order to solve this problem, this paper proposes an authentication method which can certificate both the digital contents and players, and prevent illegal reproduction without the certification server. The proposed scheme is secure in the replay attack, the man in the middle attack, and data substitution attack.

• 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.