• Title/Summary/Keyword: Hash

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Improved An RFID Mutual Authentication Protocol Based on Hash Function (개선된 해시기반의 RFID 상호인증 프로토콜)

  • Shin, Ju-Seok;Oh, Se-Jin;Jeong, Cheol-Ho;Chung, Kyung-Ho;Ahn, Kwang-Seon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.3C
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    • pp.241-250
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    • 2012
  • In 2010, Jeon-Kim proposed HMAP(Hash-based Mutual Authentication Protocol for RFID Environment) to resolve a variety of problem related to security using Mutual authentication scheme, the hash function and secret key is used to update in RFID system. Jeon-Kim proved RMAP was safe for a variety of attacks including eavesdropping attacks through safety analysis. However, unlike the claims of the proposed protocol is vulnerable to next session of the secret key exposure due to eavesdropping. In this paper, we analyze the problem of RMAP and proves it through security analysis. And we also propose improved an RFID Mutual Authentication Protocol based on Hash Function to solve problems of HMAP.

A Scheme of Computational Time Reduction on Back-End Server Using Computational Grid (계산 그리드를 이용한 백엔드 서버의 계산시간 단축 방안)

  • Hong, Seong-Pyo;Han, Seung-Jo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.12
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    • pp.2695-2701
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    • 2012
  • We need privacy protection protocols, that satisfy three essential security requirements; confidentiality, indistinguishability and forward security, in order to protect user's privacy in RFID system. The hash-chain based protocol that Ohkubo et. al proposed is the most secure protocol, that satisfies all of the essential security requirements, among existing protocols. But, this protocol has a disadvantage that it takes very long time to identify a tag in the back-end server. In this paper, we propose a scheme to keep security just as it is and to reduce computation time for identifying a tag in back-end server. The proposed scheme shows the results that the identification time in back-end server is reduced considerably compared to the hash-chain based protocol.

A Study on the Providing the Integrity of Digital Evidence while Deleting the irrelevant File (디지털 이미지 증거에서 사건과 무관한 파일 삭제시 무결성 제공 방안 연구)

  • Kim, TaeKyung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.15 no.4
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    • pp.111-116
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    • 2019
  • The digital forensic analysis ensures the integrity of confiscated data by calculating hash values for seizure and search of digital evidence and receiving confirmation and signature from participants. However, evidence that is irrelevant to the alleged offense needs to be deleted even after seizure from the point of view of privacy. But the hash value is altered by deleting the irrelevant data from the image file, one will not be able to prove that the file is in the initial state when it was seized. Therefore, in this paper, a study was conducted to support the integrity of the digital evidence, even if some of the seized digital evidence was deleted or damaged during the seizure search. The hash value of each data is calculated and hash value of the combination of hash values are also calculated. Even if the unrelated evidence is deleted from the seized evidence regardless of file system such as FAT or NTFS, the suggested method presented a way to provide the integrity that proves there is no change in the evidence file.

Hash Function-based Secure Authentication Protocol for Improving Efficiency in RFID System (효율성을 고려한 해시 함수 기반의 안전한 RFID 인증 프로토콜)

  • Kim, Ik-Su
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.4B
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    • pp.428-434
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    • 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.

Cryptanalysis of a Hash Function Proposed at PKC'98 (PKC'98에 제안된 해쉬함수의 공격)

  • 한대완;박상우;지성택
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.11 no.6
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    • pp.127-134
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    • 2001
  • At PKC\`98, SangUk Shin et al. proposed a new hash function based on advantages of SHA-1, RIPEMD-160, and HAVAL. They claimed that the Boolean functions of the hash function have good properties including the SAC(Strict Avalanche Criterion). In this paper, we first show that some of Boolean functions which are used in Shin\`s hash function does not satisfy the SAC, and then argue that satisfying the SAC may not be a good property of Boolean functions, when it is used for constructing compress functions of a hash function.

Survey on Hash-Based Post-Quantum Digital Signature Schemes (해시 기반 양자내성 전자서명 기법 연구 동향)

  • Lee, Jae-Heung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.4
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    • pp.683-688
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    • 2021
  • Digital signature algorithms such as RSA and ECDSA are threatened by the development of quantum computer technology, which is attracting attention as a future technology. Alternatively, various post-quantum algorithms such as grid-based, multivariate-based, code-based, and hash-based are being studied. Among them, the hash-based is a fast and quantitative security level that can be calculated and its safety has been proven. So it is receiving a lot of attention. In this paper, we examine various hash-based digital signature algorithms that have been proposed so far, and analyze their features and their strengths and weaknesses. In addition, we emphasize the importance of reducing the size of the signature in order for the hash-based signature algorithm to be practically used.

A Small-Area Hardware Implementation of Hash Algorithm Standard HAS-160 (해쉬 알고리듬 표준 HAS-l60의 저면적 하드웨어 구현)

  • Kim, Hae-Ju;Jeon, Heung-Woo;Shin, Kyung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.3
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    • pp.715-722
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    • 2010
  • This paper describes a hardware design of hash function processor which implements Korean Hash Algorithm Standard HAS-160. The HAS-160 processor compresses a message with arbitrary lengths into a hash code with a fixed length of 160-bit. To achieve high-speed operation with small-area, arithmetic operation for step-operation is implemented by using a hybrid structure of 5:3 and 3:2 carry-save adders and carry-select adder. It computes a 160-bit hash code from a message block of 512 bits in 82 clock cycles, and has 312 Mbps throughput at 50 MHz@3.3-V clock frequency. The designed HAS-160 processor is verified by FPGA implementation, and it has 17,600 gates on a layout area of about $1\;mm^2$ using a 0.35-${\mu}m$ CMOS cell library.

A Study on the Secure Double Pipe Hash Function (안전한 이중 파이프 해쉬함수에 관한 연구)

  • Kim, Hie-Do
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.6
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    • pp.201-208
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    • 2010
  • The classical iterated hash function is vulnerable to a multi-collision attack. Gauravaram et al. proposed 3C and 3C+ hash functions, in which an accumulation chain is added to usual Merkle-Damgard changing. Their goal is to design composition schemes resistant to generic attacks of Joux's type, but Joscak and Tuma have shown that 3C and 3C+ schemes are not better than Merkle-Damgard scheme in term of security against multi-collision attacks under some mild assumptions. In this dissertation, in order to increase security of 3C hash function, we proposed secure double pipe hash function which was effectively using XOR and XNOR operations per blocks of message. We seek to improve on the work of Lucks in a way. Proposed secure double pipe hash function takes resistance to multi-block collision, fixed point and pre-image attacks.

A Micro-Payment Protocol based on PayWord for Multiple Payments (다중 지불이 가능한 PayWord 기반의 소액 지불 프로토콜)

  • 김선형;김태윤
    • Journal of KIISE:Information Networking
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    • v.30 no.2
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    • pp.199-206
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    • 2003
  • one of the representative micropayment protocols. The original PayWord system is designed for a user who generates paywords by performing hash chain operation for payment to an only designated vendor. In other words, a user has to create new hash chain values in order to establish commercial transactions with different vendors on the Internet. Therefore, we suggest an efficient scheme that is able to deal with business to different vendors by using only one hash chain operation to supplement this drawback. In this proposed system, a broker creates a new series of hash chain values along with a certificate for the user's certificate request. This certificate is signed by a broker to give authority enabling a user to generate hash chain values. hew hash chain values generated by a broker provide means to a user to do business with multiple vendors.

Problems of certificate status validation methods using hash chain and their countermeasure (해쉬체인을 이용한 인증서 상태 검증 방법들의 문제점과 해결 방법)

  • Kang, Hyun-Joong;Ahn, Jeong-Hee
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.1
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    • pp.161-167
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    • 2008
  • As the authentication and the integrity methods based on the hash chain are popular, several certificate status validation methods based on the same function are proposd at the moment. In NOVOMODO, a CA generates and releases the hash value to each user. In Jianying Zhou's framework and Jong-Phil Yang's framework, a user generates and releases the hash value to verifier. Therefore, the CA loads are distributed to each user. However, these frameworks are based on the assumption that the CA's secret key is not lost or compromised and the certificates issued by the CA are error-free. Therefore, these frameworks are not suitable in real PKI environments. In this paper, as one hash value generated by CA is included in the user's certificate in addition, the certificate revocation published by CA using that value can be managed. The hash value included in user's certificate is the same for all users. The computation costs, the storage amounts and the release costs are small in the CA. And we modify the procedure for the signature and its validation in Jong-Phil Yang's framework. Our solution is more suitable than those frameworks in real PKI environments.

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