{"id":424,"date":"2024-07-16T14:56:59","date_gmt":"2024-07-16T05:56:59","guid":{"rendered":"https:\/\/lbcsultan.wordpress.com\/?page_id=424"},"modified":"2024-07-16T14:56:59","modified_gmt":"2024-07-16T05:56:59","slug":"thesis-2","status":"publish","type":"page","link":"https:\/\/cris.joongbu.ac.kr\/?page_id=424","title":{"rendered":"Thesis"},"content":{"rendered":"\n


PhD Thesis, ICU, 2002<\/strong><\/p>\n\n\n\n

Title: Zero-knowledge Proofs, Digital Signature Variants, and Their Applications<\/p>\n\n\n\n

Advisor: Prof. Kwangjo Kim<\/p>\n\n\n\n

Abstract:<\/p>\n\n\n\n

A protocol is a series of steps, involving two or more entities, designed to accomplish a task. If mistrusting entities interact in non-face-to-face way over an open network environment, such as the Internet, various security requirements can occur, and they can be satisfied by using cryptographic technologies. A cryptographic protocol is a protocol that uses cryptography to achieve the task and to satisfy security requirements together.<\/p>\n\n\n\n

Recently, with the advance of the Internet, many traditional off-line services, such as voting, cash, and auction, are moving to online services over the Internet. Because these real world applications are familiar with us, various and complicated security requirements are already existent. To satisfy them, proper cryptographic primitive technologies should be used in well-designed way. Efficiency or performance issue is also very important in the real world. To improve efficiency, some application protocols are designed assuming the existence of trusted third party (TTP) who provides special service. Note that TTP is very familiar experience in our real world. But, in non-face-to-face interaction over an open network environment, trusting somebody over the network is difficult, therefore reducing the trustedness on TTP is an important research issue.<\/p>\n\n\n\n

In this thesis, we try to review recent active researches on real world cryptographic protocols, such as electronic voting, electronic auction, mobile agent, and fair exchange, with focus on their security requirements and performances. We also try to point out their possible security problems and give better designs which can solve these problems. As applications of zero-knowledge proofs, we consider secrecy and verifiability in matchmaking protocol, receipt-freeness in electronic voting protocol, and anonymity and verifiability in public auction protocol. As applications of digital signature variants, we consider strong undeniability and fairness in mobile agent and fairness in the exchange protocol of digital signatures.<\/p>\n\n\n\n

Zero-knowledge proofs (ZKP) are fundamental cryptographic primitives for multi-party computation and cryptographic protocols. Using these primitives, a prover can convince a verifier that he knows some secret information without exposing it. We review various ZKP techniques and consider divertible ZKP protocols. First, we design a secure matchmaking protocol in which matched couples are found among two groups of participants without exposing the choices of participants. Second, we apply ZKP techniques to construct a receipt-free electronic voting protocol in which divertible ZKPs and designated-verifier ZKPs provide receipt-freeness. Third, we construct an efficient public auction protocol using signature of knowledge and revocable anonymous signature scheme.<\/p>\n\n\n\n

Proxy signatures are useful variants of digital signature in which an original signer delegates her signing capability to a proxy signer, and then the proxy signer signs messages on behalf of the original signer. In this study we show several weaknesses of previously proposed proxy signature schemes and propose a general method to construct strong proxy signatures (SPS). We present construction examples of Schnorr-based SPS and RSA-based SPS, and prove that the proposed SPS schemes are as secure as the original signature schemes. We apply SPS to various applications such as secure mobile agent, multi-proxy signature, and partially blind signature.<\/p>\n\n\n\n

To implement fair exchange of digital signatures, we need an efficient scheme to commit a digital signature safely to a specific receiver. To satisfy this security requirement in an efficient manner, we introduce a new variant of digital signature called conditional signature which is a specially interpreted signature on a message and a condition together. By imposing a signer-chosen condition which describes expected action of a specified receiver, conditional signature can be used as a private negotiation statement in two-party communication. We model negotiation problem using conditional signature and then construct a fair exchange protocol. We show that matching negotiation and real exchange give a fair exchange of digital signatures.<\/p>\n\n\n\n

\uc694 \uc57d<\/p>\n\n\n\n

\ud504\ub85c\ud1a0\ucf5c\uc774\ub780 \ub458 \uc774\uc0c1\uc758 \uac1c\uccb4\uac04\uc5d0 \ud2b9\uc815 \uc791\uc5c5\ubaa9\ud45c\ub97c \uc218\ud589\ud558\uae30 \uc704\ud574 \uc124\uacc4\ub41c \uc77c\ub828\uc758 \uc791\uc5c5\ub2e8\uacc4\ub97c \ub9d0\ud55c\ub2e4. \uc778\ud130\ub137\uacfc \uac19\uc740 \uac1c\ubc29\ud615 \ube44\ub300\uba74 \ub124\ud2b8\uc6cd \ud658\uacbd\uc5d0\uc11c \uc0c1\ud638 \uc2e0\ub8b0\ud558\uc9c0 \ubabb\ud558\ub294 \uac1c\uccb4\uac04\uc5d0 \ud1b5\uc2e0\uc774 \uc774\ub8e8\uc5b4\uc9c4\ub2e4\uba74 \uc5ec\ub7ec\uac00\uc9c0 \ubcf4\uc548 \uc694\uad6c\uc0ac\ud56d\ub4e4\uc774 \uc81c\uae30\ub418\uba70 \uc774\ub4e4\uc740 \uc554\ud638\uae30\uc220\uc744 \uc774\uc6a9\ud558\uc5ec \ud574\uacb0\ub420 \uc218 \uc788\ub2e4. \uc554\ud638\ud504\ub85c\ud1a0\ucf5c\uc774\ub780 \uc791\uc5c5\ubaa9\ud45c\uc640 \ubcf4\uc548\uc694\uad6c\uc0ac\ud56d\ub4e4\uc744 \ud568\uaed8 \ub9cc\uc871\uc2dc\ud0a4\uae30 \uc704\ud558\uc5ec \uc554\ud638\uae30\uc220\uc744 \uc774\uc6a9\ud558\ub294 \ud504\ub85c\ud1a0\ucf5c\uc744 \ub9d0\ud55c\ub2e4.<\/p>\n\n\n\n

\ucd5c\uadfc \uc778\ud130\ub137\uc758 \ubc1c\uc804\uc5d0 \ub530\ub77c \ud22c\ud45c, \ud604\uae08, \uacbd\ub9e4 \ub4f1 \uae30\uc874\uc758 \ub9ce\uc740 \uc624\ud504\ub77c\uc778 \uc11c\ube44\uc2a4\ub4e4\uc774 \uc778\ud130\ub137\uc0c1\uc758 \uc628\ub77c\uc778 \uc11c\ube44\uc2a4\ub85c \uc804\ud658\ub418\uace0 \uc788\ub2e4. \uc774\ub7ec\ud55c \uc2e4\uc0dd\ud65c \uc751\uc6a9\ubd84\uc57c\ub294 \uc6b0\ub9ac\uac00 \uc774\ubbf8 \uc775\uc219\ud558\uac8c \uc774\uc6a9\ud558\uace0 \uc788\uae30 \ub54c\ubb38\uc5d0 \ub9ce\uc740 \ubcf5\uc7a1\ud55c \ubcf4\uc548\uc694\uad6c\uc0ac\ud56d\ub4e4\uc774 \uc874\uc7ac\ud55c\ub2e4. \uc774\ub4e4\uc744 \ub9cc\uc871\uc2dc\ud0a4\ub824\uba74 \uc751\uc6a9\uc11c\ube44\uc2a4\ub294 \uc5ec\ub7ec\uac00\uc9c0 \uc554\ud638\uae30\ubc18\uae30\uc220\ub4e4\uc744 \uc774\uc6a9\ud558\uc5ec \uc138\uc2ec\ud558\uac8c \uc124\uacc4\ub418\uc5b4\uc57c \ud55c\ub2e4. \ud6a8\uc728\uc131\uc740 \uc2e4\uc0dd\ud65c \uc751\uc6a9\ubd84\uc57c\uc5d0\uc11c \ub9e4\uc6b0 \uc911\uc694\ud55c \uc694\uc18c\uc911 \ud558\ub098\uc774\ub2e4. \ud6a8\uc728\uc131\uc744 \ub192\uc774\uae30 \uc704\ud574\uc11c \uc5b4\ub5a4 \uc751\uc6a9 \uc11c\ube44\uc2a4\ub4e4\uc740 \uc2e0\ub8b0\uae30\uad00\uc744 \uac00\uc815\ud558\uc5ec \uc774\ub97c \uae30\ubc18\uc73c\ub85c \uc124\uacc4\ub418\uae30\ub3c4 \ud55c\ub2e4. \uc2e0\ub8b0\uae30\uad00\uc740 \uc2e4\uc138\uacc4\uc5d0\uc11c \ub9e4\uc6b0 \uc775\uc219\ud55c \uac1c\ub150\uc774\ub2e4. \uadf8\ub7ec\ub098 \ube44\ub300\uba74\uc758 \uac1c\ubc29\ud615 \ub124\ud2b8\uc6cd \ud658\uacbd\uc5d0\uc11c \ub124\ud2b8\uc6cd\uc0c1\uc5d0 \uc874\uc7ac\ud558\ub294 \ud2b9\uc815 \uac1c\uccb4\ub97c \uc2e0\ub8b0\ud55c\ub2e4\ub294 \uac83\uc740 \uc5b4\ub824\uc6b4 \ubb38\uc81c\ub77c\uace0 \ubcfc \uc218 \uc788\uae30 \ub54c\ubb38\uc5d0 \uc2e0\ub8b0\uae30\uad00\uc5d0\uc758 \uc758\uc874\uc744 \uc904\uc774\ub294 \uac83\ub3c4 \uc911\uc694\ud55c \uc5f0\uad6c \uc774\uc288\uc911\uc758 \ud558\ub098\uc774\ub2e4.<\/p>\n\n\n\n

\uc774 \ub17c\ubb38\uc5d0\uc11c\ub294 \uc804\uc790\ud22c\ud45c, \uc804\uc790\uacbd\ub9e4, \uc774\ub3d9\uc5d0\uc774\uc804\ud2b8 \ub4f1 \ud604\uc7ac \ud65c\ubc1c\ud788 \uc5f0\uad6c\ub418\uace0 \uc788\ub294 \uc2e4\uc0dd\ud65c \uc554\ud638\ud504\ub85c\ud1a0\ucf5c\ub4e4\uc5d0 \ub300\ud55c \uae30\uc874 \uc5f0\uad6c\ub4e4\uc744 \ubd84\uc11d\ud558\uc600\uc73c\uba70 \ud2b9\ud788 \ubcf4\uc548\uc694\uad6c\uc0ac\ud56d\uacfc \ud6a8\uc728\uc131\uc5d0 \ucd08\uc810\uc744 \ub450\uace0 \ubd84\uc11d\ud558\uc600\ub2e4. \uae30\uc874 \uc5f0\uad6c\ub4e4\uc758 \ubcf4\uc548\uc0c1 \ubb38\uc81c\uc810\uc744 \uc9c0\uc801\ud558\uace0 \uc774\ub4e4\uc744 \ud574\uacb0\ud560 \uc218 \uc788\ub294 \uac1c\uc120\ub41c \uc554\ud638\ud504\ub85c\ud1a0\ucf5c\uc744 \uc81c\uc548\ud558\uace0\uc790 \ud558\uc600\ub2e4. \uc601\uc9c0\uc2dd \uc99d\uba85\uc758 \uc751\uc6a9\ubd84\uc57c\ub85c\uc11c \uc804\uc790\uc911\ub9e4 \ud504\ub85c\ud1a0\ucf5c\uc5d0\uc11c\uc758 \uae30\ubc00\uc131\uacfc \uac80\uc99d\uc131, \uc804\uc790\ud22c\ud45c \ud504\ub85c\ud1a0\ucf5c\uc5d0\uc11c\uc758 \ub9e4\ud45c\ubc29\uc9c0 \uae30\ub2a5, \uc804\uc790\uacbd\ub9e4 \ud504\ub85c\ud1a0\ucf5c\uc5d0\uc11c\uc758 \uc775\uba85\uc131\uacfc \uc804\uccb4\uac80\uc99d\uc131\uc5d0 \ub300\ud574 \uc5f0\uad6c\ud558\uc600\ub2e4. \ub610\ud55c \ubcc0\ud615 \uc804\uc790\uc11c\uba85\uae30\ubc95\uc758 \uc751\uc6a9\ubd84\uc57c\ub85c\uc11c \uc774\ub3d9\uc5d0\uc774\uc804\ud2b8\uc5d0\uc11c\uc758 \ubd80\uc778\ubc29\uc9c0 \ubc0f \uacf5\uc815\uc131, \uacf5\uc815\ud55c \uc11c\uba85\uad50\ud658 \ud504\ub85c\ud1a0\ucf5c\uc5d0 \ub300\ud574 \uc5f0\uad6c\ud558\uc600\ub2e4.<\/p>\n\n\n\n

\uc601\uc9c0\uc2dd \uc99d\uba85\uc740 \ub2e4\uc790\uac04 \uacc4\uc0b0\uacfc \uc554\ud638\ud504\ub85c\ud1a0\ucf5c\uc744 \uc124\uacc4\ud558\uae30 \uc704\ud55c \ud575\uc2ec \uc554\ud638\uae30\ubc18\uae30\uc220\uc911\uc758 \ud558\ub098\uc774\ub2e4. \uc601\uc9c0\uc2dd \uc99d\uba85 \uae30\ubc95\uc744 \uc774\uc6a9\ud558\uba74 \uc99d\uba85\uc790\ub294 \uac80\uc99d\uc790\uc5d0\uac8c \ube44\ubc00\uc815\ubcf4\ub97c \ub178\ucd9c\uc2dc\ud0a4\uc9c0 \uc54a\uace0\ub3c4 \uadf8 \uc815\ubcf4\ub97c \uc54c\uace0 \uc788\ub2e4\ub294 \uc0ac\uc2e4\uc744 \uc99d\uba85\ud560 \uc218 \uc788\ub2e4. \uc5ec\uae30\uc5d0\uc11c\ub294 \ub2e4\uc591\ud55c \uc601\uc9c0\uc2dd \uc99d\uba85 \uae30\ubc95\ub4e4\uc5d0 \ub300\ud574 \uc0b4\ud3b4\ubcf4\uace0 \ubcc0\ud658\ud615 \uc601\uc9c0\uc2dd \uc99d\uba85 \uae30\ubc95(divertible ZKP)\uc744 \uace0\ub824\ud55c\ub2e4. \uccab\ubc88\uc9f8 \uc751\uc6a9\uc73c\ub85c \ub450\uac1c\uc758 \ucc38\uc5ec\uc790 \uadf8\ub8f9 \uc0ac\uc774\uc5d0 \ucc38\uc5ec\uc790\ub4e4\uc758 \uc120\ud0dd\uc744 \ub178\ucd9c\uc2dc\ud0a4\uc9c0 \uc54a\uace0 \ucee4\ud50c\uc744 \ucc3e\uc544\ub0b4\ub294 \uc548\uc804\ud55c \uc804\uc790\uc911\ub9e4 \ud504\ub85c\ud1a0\ucf5c\uc744 \uc124\uacc4\ud558\uc600\ub2e4. \ub458\uc9f8, \ubcc0\ud658\ud615 \uc601\uc9c0\uc2dd \uc99d\uba85\uae30\ubc95\uacfc \uac80\uc99d\uc790\uc9c0\uc815 \uc601\uc9c0\uc2dd \uc99d\uba85(designated-verifier ZKP)\uc744 \uc774\uc6a9\ud55c \ub9e4\ud45c\ubc29\uc9c0 \uac00\ub2a5\ud55c \uc804\uc790\ud22c\ud45c \ud504\ub85c\ud1a0\ucf5c\uc744 \uc124\uacc4\ud558\uc600\ub2e4. \uc138\uc9f8, \uc601\uc9c0\uc2dd\uc11c\uba85(signature of knowledge)\uacfc \uc775\uba85\uc131\ucde8\uc18c \uac00\ub2a5\ud55c \uc775\uba85\uc804\uc790\uc11c\uba85\uc744 \uc774\uc6a9\ud558\uc5ec \ud6a8\uc728\uc801\uc778 \uacf5\uac1c\uacbd\ub9e4 \ud504\ub85c\ud1a0\ucf5c\uc744 \uc124\uacc4\ud558\uc600\ub2e4.<\/p>\n\n\n\n

\ub300\ub9ac\uc11c\uba85\uc740 \uc6d0\uc11c\uba85\uc790\uac00 \ub300\ub9ac\uc11c\uba85\uc790\uc5d0\uac8c \uc11c\uba85\ub2a5\ub825\uc744 \uc704\ud0c1\ud558\uace0 \ub300\ub9ac\uc11c\uba85\uc790\ub294 \uc6d0\uc11c\uba85\uc790\ub97c \ub300\uc2e0\ud558\uc5ec \uc11c\uba85\uc744 \uc0dd\uc131\ud560 \uc218 \uc788\ub294 \ubcc0\ud615 \uc804\uc790\uc11c\uba85 \uae30\ubc95\uc774\ub2e4. \uc5ec\uae30\uc5d0\uc11c\ub294 \uae30\uc874\uc758 \ub300\ub9ac\uc11c\uba85 \uae30\ubc95\ub4e4\uc758 \ucde8\uc57d\uc810\uc744 \uc81c\uc2dc\ud558\uace0 \uc774\ub4e4\uc744 \ud574\uacb0\ud560 \uc218 \uc788\ub294 \uac15\ud55c\ub300\ub9ac\uc11c\uba85\uc744 \uad6c\uc131\ud558\ub294 \uc77c\ubc18\uc801\uc778 \uae30\ubc95\uc744 \uc81c\uc2dc\ud55c\ub2e4. \uadf8 \uc0ac\ub840\ub85c\uc11c Schnorr \uc11c\uba85\uacfc RSA \uc11c\uba85\uc5d0 \uae30\ubc18\ud55c \uac15\ud55c\ub300\ub9ac\uc11c\uba85 \uae30\ubc95\uc744 \uc81c\uc2dc\ud55c\ub2e4. \uc544\uc6b8\ub7ec \uc774\ub4e4\uc744 \uc548\uc804\ud55c \uc774\ub3d9\uc5d0\uc774\uc804\ud2b8, \ubcf5\uc218\ub300\ub9ac\uc11c\uba85, \ubd80\ubd84\uc740\ub2c9\uc11c\uba85 \ub4f1\uc5d0 \uc801\uc6a9\ud558\uc600\ub2e4.<\/p>\n\n\n\n

\uacf5\uc815\ud55c \uc804\uc790\uc11c\uba85 \uad50\ud658 \ud504\ub85c\ud1a0\ucf5c\uc744 \uad6c\uc131\ud558\uae30 \uc704\ud574\uc11c\ub294 \uc804\uc790\uc11c\uba85\uc744 \ud2b9\uc815 \uc218\uc2e0\uc790\uc5d0\uac8c \uc548\uc804\ud558\uac8c \uc704\ud0c1(commit)\ud558\ub294 \uae30\ubc95\uc774 \ud544\uc694\ud558\ub2e4. \uc774\ub97c \uad6c\ud604\ud558\uae30 \uc704\ud574 \uc870\uac74\ubd80 \uc11c\uba85\uc774\ub77c\ub294 \uc0c8\ub85c\uc6b4 \uac1c\ub150\uc744 \uc81c\uc2dc\ud558\uc600\ub2e4. \uc774\uac83\uc740 \uc11c\uba85\uc790\uac00 \ud2b9\uc815 \uc218\uc2e0\uc790\uc5d0\uac8c \uba54\uc2dc\uc9c0\uc5d0 \ub300\ud55c \uc11c\uba85\uc744 \uc870\uac74\ubd80\ub85c \uc704\ud0c1\ud558\ub294 \ubc29\ubc95\uc774\ub2e4. \uc11c\uba85\uc790\uac00 \ud2b9\uc815 \uc218\uc2e0\uc790\uc5d0 \ub300\ud574 \uc11c\uba85\uc744 \uc704\ud0c1\ud558\uba74\uc11c \uc870\uac74\uc744 \uc9c0\uc815\ud560 \uc218 \uc788\uae30 \ub54c\ubb38\uc5d0 \uc870\uac74\ubd80 \uc11c\uba85\uc740 \uac1c\uc778\uac04\uc758 \uad50\uc12d(negotiation) \ub610\ub294 \ud765\uc815\uc758 \ubaa9\uc801\uc744 \uc704\ud574 \uc0ac\uc6a9\ub420 \uc218 \uc788\ub2e4. \ubcf8 \uc5f0\uad6c\uc5d0\uc11c\ub294 \uad50\uc12d \ud504\ub85c\ud1a0\ucf5c\uc744 \uc870\uac74\ubd80 \uc11c\uba85\uc744 \uc774\uc6a9\ud558\uc5ec \ubaa8\ub378\ub9c1\ud558\uc600\uace0 \uc774\ub97c \uae30\ubc18\uc73c\ub85c \uacf5\uc815\ud55c \uc804\uc790\uc11c\uba85 \uad50\ud658 \ud504\ub85c\ud1a0\ucf5c\uc744 \uad6c\uc131\ud558\uc600\ub2e4. \uad50\uc12d\uc744 \uc644\ub8cc\ud55c \ud6c4 \uc774\uc5d0 \uae30\ubc18\ud558\uc5ec \uc11c\uba85\uc744 \uad50\ud658\ud568\uc73c\ub85c\uc368 \uacf5\uc815\ud55c \uc804\uc790\uc11c\uba85 \uad50\ud658\uc774 \uac00\ub2a5\ud568\uc744 \ubcf4\uc600\ub2e4.<\/p>\n\n\n\n

Download : PhD Thesis<\/a><\/p>\n\n\n\n

\n\n\n\n

Master Thesis, \uc11c\uc6b8\ub300\ud559\uad50 \ubb3c\ub9ac\ud559\uacfc, 1988<\/strong><\/p>\n\n\n\n

Title: Electrical Transport of Polymer TCNQ Complex Salts and Its Monomeric Model Compounds<\/p>\n\n\n\n

Advisor: Yungwoo Park<\/p>\n\n\n\n

Download: Master Thesis<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

PhD Thesis, ICU, 2002 Title: Zero-knowledge Proofs, Digital Signature Variants, and Their Applications Advisor: Prof. Kwangjo Kim Abstract: A protocol is a series of steps, involving two or more entities, designed to accomplish a task. If mistrusting entities interact in non-face-to-face way over an open network environment, such as the Internet, various security requirements can … \ub354 \ubcf4\uae30 “Thesis”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-424","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=\/wp\/v2\/pages\/424","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=424"}],"version-history":[{"count":0,"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=\/wp\/v2\/pages\/424\/revisions"}],"wp:attachment":[{"href":"https:\/\/cris.joongbu.ac.kr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}