• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38B no.5
• /
• pp.377-384
• /
• 2013

In order to improve the security strength in the password based user authentication, in which the security vulnerability is increased while the same password is repeatedly used, the OTP(One-Time Password) system has been introduced. In the OTP systems, however, the user account information and OTP value may be hacked if the user PC is infected by the malicious codes, because the user types the OTP value, which is generated by the mobile device synchronized with the server, directly onto the user PC. In this paper, we propose a new method, called DTOTP(Dual Transmission OTP), to solve this security problem. The DTOTP system is an improved two-factor authentication method by using the dual transmission, in which the user performs the server authentication by typing the user account and password information onto the PC, and then for the OTP authentication the mobile device scans the QR code displayed on the PC and the OTP value is sent to the server directly. The proposed system provides more improved security strength than that of the existing OTP system, and also can adopt the existing OTP algorithm without any modification. As a result, the proposed system can be safely applied to various security services such like banking, portal, and game services.

• ETRI Journal
• /
• v.33 no.4
• /
• pp.611-620
• /
• 2011

Since card-type one-time password (OTP) generators became available, power and area consumption has been one of the main issues of hardware OTPs. Because relatively smaller batteries and smaller chip areas are available for this type of OTP compared to existing token-type OTPs, it is necessary to implement power-efficient and compact dedicated OTP hardware modules. In this paper, we design and implement a low-power small-area hardware OTP generator based on the Advanced Encryption Standard (AES). First, we implement a prototype AES hardware module using a 350 nm process to verify the effectiveness of our optimization techniques for the SubBytes transform and data storage. Next, we apply the optimized AES to a real-world OTP hardware module which is implemented using a 180 nm process. Our experimental results show the power consumption of our OTP module using the new AES implementation is only 49.4% and 15.0% of those of an HOTP and software-based OTP, respectively.

• Journal of KIISE:Computer Systems and Theory
• /
• v.29 no.5
• /
• pp.291-298
• /
• 2002

Mutual authentication is essential for key exchange protocols and password-based authentication scheme is used widely, which is convenient to users and executed on the cheap. Password-based protocol should be not only secure against attach but also efficient to reduce user's load. In this paper, we propose a new key exchange protocol, called OTP-EKE(One Time Password based Encrypted Key Exchange), to provide authentication and to share a session key between a server and a user. We choose a password-based scheme as a user authentication. Especially, we use a one-time-password verifier and server's public password to protect against attacks on server's directory. As for efficiency, we improve the performance by reducing the number of modular exponentiations and the number of rounds.

• Convergence Security Journal
• /
• v.18 no.2
• /
• pp.11-17
• /
• 2018

Lamport's one-time password (OTP) was originally proposed to address the weaknesses of a simple password system: fixed password, pre-shared password. However, a main weakness of Lamport's OTP is that a root hash value of a new hash chain should be re-registered after consuming all the hash values since OTP generation is based on the finite hash chain. Several studies have been conducted to solve these drawbacks, but new drawbacks such as increased burden of proof for verifiers and verifiers have been exposed. In this paper, we propose and compare a novel OTP that overlaps several short hash chains instead of one long hash chain, which is the core of existing Lamport OTP, to solve the drawbacks while maintaining the advantages of Lamport.

• Journal of the Optical Society of Korea
• /
• v.20 no.6
• /
• pp.722-732
• /
• 2016

A new optical one-time password (OTP) authentication method using digital holography is proposed, which enhances security strength in the authentication system. A challenge-response optical OTP algorithm based on two-factor authentication is presented using two-step phase-shifting digital holography, and two-way authentication is also performed using challenge-response handshake in both directions. Identification (ID), password (PW), and OTP are encrypted with a shared key by applying phase-shifting digital holography, and these encrypted pieces of information are verified by each party by means of the shared key. The encrypted digital holograms are obtained by Fourier-transform holography and are recorded on a CCD with 256 quantized gray-level intensities. Because the intensity pattern of such an encrypted digital hologram is distributed randomly, it guards against a replay attack and results in higher security level. The proposed method has advantages, in that it does not require a time-synchronized OTP, and can be applied to various authentication applications. Computer experiments show that the proposed method is feasible for high-security OTP authentication.

• The KIPS Transactions:PartC
• /
• v.17C no.4
• /
• pp.361-370
• /
• 2010

OTP(One Time Password) is a user authentication using secure mechanism to authenticate each other in a way to generate a password, an attacker could intercept the password to masquerade as legitimate users is a way to prevent attacks. The OTP can be implemented as H/W or S/W. Token and card type OTP, implemented as H/W, is difficult to popularize because of having problem with deployment and usability. As a way to replace it implemented as S/W on Mobile or PC is introduced. However, S/W products can be target of malicious attacks if S/W products have vulnerability of implementation. In fact, FSA said the OTP implemented on a mobile have vulnerability of implementation. However, the OTP implemented on a PC have no case about analysis of vulnerability. So, in this paper derive security review and vulnerabilities analysis of implemented on a PC.

• Journal of Digital Convergence
• /
• v.13 no.1
• /
• pp.283-288
• /
• 2015

A disposable password is necessary to avoid any danger by the use of a static password and reinforce the user's authentication. In order to prevent personal information from being exposed, OTP generation algorithm is regarded as important. The OTP generation algorithm we suggest in this thesis generates 256-bit-size OTP Data by using Seed value and Time value. This value that the generated OTP Data are arranged with a matrix and a 32-bit-value is extracted on an irregular basis becomes the final value. We can find out that the more OTP generation frequency we have, the lower probability of clash tolerance we get in our suggested algorithm, compared to the previous algorithm.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.6
• /
• pp.27-32
• /
• 2009

Recently, most of information services are provided by the computer network, since the technology of computer communication is developing rapidly, and the worth of information over the network is also increasing with expensive cost. But various attacks to quietly intercept the informations is invoked with the technology of communication developed, and then most of the financial agency currently have used OTP, which is generated by a token at a number whenever a user authenticates to a server, rather than general static password for some services. A 2-Factor OTP generating method using the OTP token is mostly used by the financial agency. However, the method is vulnerable to real attacks and therefore the OTP token could be robbed and disappeared. In this paper, we propose a 3-Factor OTP way using HMAC to conquer the problems and analyze the security of the proposed scheme.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2014.01a
• /
• pp.263-265
• /
• 2014

본 논문에서는 OTP를 이용한 사용자 계정 로그인 정보 관리 시스템 구현을 제안한다. 웹에서 패스워드(PW)를 통해 인증을 하는 대부분의 사용자는 편리를 위해 단순한 패스워드를 설정한다. 하지만 단순한 패스워드는 추측 공격 등 해킹 당할 위험이 높다. 그러므로 제시하고자 하는 시스템은 로그인 정보 중 ID와 PW를 복잡하게 설정하고 체계적으로 관리하여 보안성과 편리성을 동시에 높이고자 한다. 또한 PW를 통한 인증 방법의 단점인 추측 공격과 스나이퍼 공격의 취약점을 보완하기 위해 OTP(One-time Password) 기술을 이용하여 보안을 강화하고자 한다.

• Convergence Security Journal
• /
• v.7 no.3
• /
• pp.101-107
• /
• 2007

In recent years, electronic financial services, such as internet banking, come into wide use since the personal computer and network technology have made reasonably good progress. The growth of electronic financial service contributes to promoting the business efficiency of financial institution and promoting the convenience of financial customer, while the security on electronic financial service is getting more important because it is not face-to-face financial service. Therefore, the financial sector had decided to introduce the OTP (One Time Password) in order to authenticate the identification of customer and has built the Integrated OTP Authentication Center for a customer being able to use only one OTP token in electronic financial transaction with several financial institution. In this paper, we introduce the business of Integrated OTP Authentication Center and present the security analysis on integrated OPT authentication service, which is the main function of Integrated OTP Authentication Center.