• Journal of the Korea Convergence Society
• /
• v.9 no.9
• /
• pp.83-88
• /
• 2018

The blockchain is the technique which is used in decentralized system instead of centralized system. Its characteristics are anonymous and transparency. However, there are still some traditional attacks. In this paper, we introduced some of the famous consensus algorithm with blockchain: Bitcoin, Algorand, and IOTA. Also, this paper talked about how each consensus algorithm tried to solve those traditional attacks such as double spending attack or sybil attack. Furthermore, if the consensus algorithm does not consider those attacks yet, then the author would introduce additional methods to solve those attacks. Furthermore, this paper proposed the new scenario that can make classical attacks be happened.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.10a
• /
• pp.263-266
• /
• 2012

This paper describes an efficient hardware implementation of Whirlpool hash function as ISO/IEC 10118-3 standard. Optimized timing is achieved by using pipelined small LUTs, and Whirlpool block cipher and key schedule have been implemented in parallel for improving throughput. In key schedule, key addition is area-optimized by using inverters and muxes instead of using rom and xor gates. This hardware has been implemented on Virtex5-XC5VSX50T FPGA device. Its maximum operating frequency is about 151MHz, and throughput is about 950Mbps.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.05a
• /
• pp.656-658
• /
• 2013

Due to increasing demand of new technology, the complexity of hardware and software consisting embedded systems is rapidly growing. Consequently, it is getting hard to design complex devices only with traditional methodology. In this contribution, I introduce a new approach of designing complex hardware with SystemVerilog. I adopted the idea of object oriented implementation of the SystemVerilog to the design of an elliptic curve crypto-engine server farm. I successfully implemented the whole system including the test bench in one integrated environment, otherwise in the traditional way it would have cost Verilog simulation and C/SystemC verification which means much more time and effort.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.27 no.2
• /
• pp.343-351
• /
• 2017

With ICT technology develops, IoT environment is attracting attention. However, IoT devices have various CPU performance as much as various purpose of use. Some IoT devices use the cpu that doesn't support public key cryptogrphy or crypto acceleration. In this paper, we study Blockchain-based IoT Device Authentication Scheme that provides authentication, integirity and non-repudation through analysis of Lamport Hash-chain, Lamport Signature, Blockchain and existing Authentication protocols. The proposed scheme requires only simple hash operation in IoT devices and it can operate in low performance IoT device, thus ensuring secure authentication in IoT environment.

• The KIPS Transactions:PartC
• /
• v.11C no.3
• /
• pp.309-318
• /
• 2004

AAAv6-based Diameter method is using in the user authentication to satisfy the users' increasing user authentication demand and to supply a safe communication between mobile node and server in the Mobile IP. therefore, In this paper, We design a model of server capacity based on EAP-TLS that in one of AAAv6 models with mobility among domains to get the optimized capacity index of the server for user authentication accomplishment. We elicitat the authentication capacity index for each server of which is accomplishing in user authentication using DSA/RSA algorithm and purpose the optimized condition for the AAAv6 capacity by the index.

• Journal of Korea Society of Industrial Information Systems
• /
• v.22 no.6
• /
• pp.17-22
• /
• 2017

In this paper, a password recognition system that can overcome a shoulder-surfing attack is developed. During the time period of password insertion, the developed system can prevent the attack and enhance the safety of the password. In order to raise the detection rate of the password image, the mopology technique is utilized. By adapting 4 times of the expansion and dilation, the niose from the binary image of the password is removed. Finally, the mobile phone application is also developed to recognize the one time password and the detection rate is measured. It is shown that the detection rate of 90% is achieved under the dark light condition.

• Journal of the Korea Society of Computer and Information
• /
• v.5 no.4
• /
• pp.13-20
• /
• 2000

There are many security problems with Electronic Commerce since insecure public networks, especially Internet, are used. Therefore, for implementing secure Electronic Commerce, CAPI(Cryptographic Application Programming Interfaces) is expected to use various form of security applications. The Cryptographic Application Programming Interface supports cryptographic services for each level and various security services. The CSSM API(Common Security Service Management Application Programming Interface) Provides modularity, simplicity, and extensibility in terms of various add-in modules and interfaces in contract to other CAPIs. This paper proposed an applying method of CSSM API having various extensibility and supporting multi-platforms to Electronic Commerce. we describe encryption, digital signature operation of CSSM API's CSP interface and evaluate secureness by matching relation of theratening factors to security services.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.4
• /
• pp.753-763
• /
• 2014

Recently financial institutions and large retailers have a large amount of personal information leakage accident occurred one after another, and the damage is a trend of increasing day by day. Regulation such as enforcing the encryption of the personal identification information are strengthened. Efficient technology to encrypt personal information is Format-preserving encryption. Typical encryption expand output data length than input data length and change a format. Format Preserving Encryption is an efficient method to minimize database and application modification, because it makes preserve length and format of input data. In this paper, to encrypt personal information efficiently, we propose newly Format Preserving Encryption using Block cipher mode of operation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.258-259
• /
• 2017

Recently, as science and technology is very growing, wire and wireless communication is merged and interconnected. Therefore, advanced internet technology allow all kinds of communication to integrate with heterogeneous device and sensors. The representative example is smart home network based on internet of things. Communication surroundings under IoT services are more complex. Conventional encryption techniques can't provide to IoT application because of its limited resources such as small memory capacity and low computing power. In this paper, we analyzed authentication procedure between home gateway and node in sensor under smart home network.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.1C
• /
• pp.24-33
• /
• 2012

Recently, the ultra-lightweight authentication RFID protocol that can actually implement on the RFID Tag is one among authentication protocols getting a concern, but recently many problems were clarified of the feature becase of the protocol which doesn't use the security algorithm. In this paper, we analyzed the problem of the ultra-lightweight authentication protocols and propose the design of ultra-lightweight RFID authentic ation protocols improving the index processing techniques. Because of improving the index processing technique in the method sending the Server authentication message to the authenticated tag, the proposed protocol is strong against the active attack which Li presents. Besides, the proposed protocol has the buffer storage of the keys and index and is strong against the asynchronous attack.