臺灣博碩士論文加值系統

在一企業或部門群體當中，對於訊息加密或是文件簽署的需求是相當重要的。小至印表機的列印要求，大至重要文件簽署或多數人簽名負責的需求，文件加密之重要性及機密性與日俱增。在群體當中只希望部分合法成員才能加解密其訊息，這些需求發展出了群體簽章(Group Signature)。此外，由於現有之靜態群體簽章過程，無法確保在簽署的過程中，若遇到異常發生時還能完成簽署的動作。因此我們利用樂觀式公平簽章方法[11]，結合短群體簽章[4]，希望能使現有短群體簽章若在雙方簽署過程中發生異常中斷時，還能確保完成剩餘的簽署過程，而且雙方能相互簽署及驗證，若需要還原身份，也只需要透過可信賴第三者(Trusted Third Party,TTP)的協助即能完成，減少TTP所擁有的群體成員訊息。

Encrypting messages or signing text is essential in daily operations of current enterprises. Depending on the importance and the secrecy of texts, group signature was developed to cope with the need for institutional contract signing rather than personal signature.
In this study, we combine the technique revealed in“The Optimistic Fair Exchange of Digital Signatures Protocol”[11] which was presented by N.Asokan、Victor Shoup and Michael Waidner and the short group signatures [4] from Dan Boneh、Xavier Boyen and Hovav Shacham to ensure the integrity of signing process and reduce the level of trust group members must put on the trusted third party (TTP).

目錄
摘要 i
ABSTRACT ii
目錄 i
圖目錄 iii
第一章 緒論 1
第一節 前言 1
一、群體簽章 1
二、公平數位簽章交換 3
三、植基於樂觀式公平數位簽章交換之短群體簽章 4
第二節 動機及目的 5
一、研究動機 5
二、研究目的 6
三、論文架構 6
第二章 文獻探討 7
第一節 靜態群體簽章 7
一、群體簽章 7
二、群體簽章的基本定義 8
三、短群體簽章 11
四、局部驗證者廢除 13
第二節 簽章交換 15
一、樂觀的公平數位簽章交換 15
二、無顧慮濫用之樂觀式合約簽署 18
第一節 研究方法 22
第二節 植基於樂觀式公平數位簽章交換之短群體簽章 24
一、雙線性群體 24
二、植基於樂觀式公平數位簽章交換之短群體簽章 24
第四章 安全性分析 29
第五章 結論 31
參考文獻 32

圖目錄

圖1 靜態群體簽章架構圖 8
圖2 JOIN PROTOCOL 11
圖3 SHORT GROUP SIGNATURE PROTOCOL 12
圖4 SIGNING PROTOCOL 13
圖5 FAIR EXCHANGE PROTOCOL 15
圖6 VERIFIABLE ENCRYPTION PROTOCOL 16
圖7 ABORT 17
圖8 B-RESOLVE 17
圖9 A-RESOLVE 18
圖10 THE BASIC ABUSE-FREE CONTRACT SIGNING PROTOCOL FOR TWO PARTIES 19
圖11 ALTERNATIVE ABUSE-FREE CONTRACT SIGNING PROTOCOL FOR TWO PARTIES 20
圖12 SECURE CONTRACT SIGNING PROTOCOL FOR THREE PARTIES 21
圖13 簽章流程圖 23
圖14 OPTIMISTIC FAIR EXCHANGE OF SHORT GROUP SIGNATURE 25
圖15 VERIFIABLE ENCRYPTION PROTOCOL 26
圖16 ABORT 27
圖17 B-RESOLVE 28
圖18 A-RESOLVE 28

[1]B. Schneier: A Primer on Authentication and Digital Signatures. Computer Security Journal, v. 10, n. 2, 1994: 38-40
[2]Dan Boneh, Ben Lynn, Hovav Shacham: Short Signatures from the Weil Pairing. J. Cryptology 17(4): 297-319 (2004)
[3]Dan Boneh, Hovav Shacham: Group signatures with verifier-local revocation. ACM Conference on Computer and Communications Security 2004: 168-177
[4]Dan Boneh, Xavier Boyen, Hovav Shacham: Short Group Signatures. CRYPTO 2004:41-55
[5]Dan Boneh, Xavier Boyen: Short Signatures Without Random Oracles. EUROCRYPT 2004: 56-73
[6]David Chaum, Eugène van Heyst: Group Signatures. EUROCRYPT 1991: 257-265
[7]Juan A. Garay, Markus Jakobsson, Philip D. MacKenzie: Abuse-Free Optimistic Contract Signing. CRYPTO 1999: 449-466
[8]Lidong Chen, Torben P. Pedersen: New Group Signature Schemes (Extended Abstract). EUROCRYPT 1994: 171-181
[9]Mihir Bellare, Daniele Micciancio, Bogdan Warinschi: Foundations of Group Signatures: Formal Definitions, Simplified Requirements, and a Construction Based on General Assumptions. EUROCRYPT 2003: 614-629
[10]Mihir Bellare, Haixia Shi, Chong Zhang: Foundations of Group Signatures: The Case of Dynamic Groups. CT-RSA 2005: 136-153
[11]N. Asokan, Victor Shoup, Michael Waidner: Optimistic Fair Exchange of Digital Signatures (Extended Abstract). EUROCRYPT 1998: 591-606