Digital Multisignature by Selective Signatories with Subject-

• Main Authors: Huang, Shih-Chan, 黃士展
• Other Authors: Wu Tzong-Chen
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/08610376019441232238

碩士 === 國立台灣工業技術學院 === 管理技術研究所 === 85 === Based on a modified ElGamal''s signature scheme, a variant ofdigital multisignature, namely the digital multisignature byselective signatories with subject- based document division, isproposed. A signing group consists of candidate signatories and eachcandidate signatory has a specific knowledge domain. Beforeconstructing a multisignature for a document with respect to thesigning group, the document dispatcher first divides the documentinto some proper subdocuments in accordance with the specificknowledge domains for the candidate signatories in the group, andthen assigns each subdocument to the corresponding candidatesignatory, namely selective signatory, who has complete justificationof the subjects within it for signing. Each selective signatory onlysigns the assigned subdocument , instead of the whole document, andconstructs a personal signature. Every personal signature can beverified by other candidate signatories. Afterwards, any candidatesignatory can collect all verified personal signatures to form amultisignature for the whole document with respect to the signinggroup. Any verifier can easily verify the multisignature using thepublic key for the selective signatory. In real applications, theproposed digital multisignature has the following advantages: (1)complete justification of the subjects in the signing document can beenhanced; (2) communication cost for document dispatch can bereduced. Most of the previously proposed digital multisignatureschemes do not have such advantages.