A Decentralized Trusted Timestamping Based on Blockchains

カテゴリ: 論文誌(論文単位)

グループ名: 【D】産業応用部門（英文）

発行日: 2017/07/01

タイトル(英語): A Decentralized Trusted Timestamping Based on Blockchains

著者名: Yuefei Gao (Department of Intelligent Interaction Technologies, University of Tsukuba), Hajime Nobuhara (Department of Intelligent Interaction Technologies, University of Tsukuba)

著者名(英語): Yuefei Gao (Department of Intelligent Interaction Technologies, University of Tsukuba), Hajime Nobuhara (Department of Intelligent Interaction Technologies, University of Tsukuba)

キーワード: trusted timestamping，blockchain，digital data protection

要約(英語): Decentralized trusted timestamping based on blockchains is used to protect a large variety of digital data. At present, in the case of trusted timestamping services, such related information is not included in the OP_RETURN field of a Bitcoin's transaction chain, which has a limited size (40 bytes). When OP_RETURN is extended, (e.g., with multiple OP_RETURN fields) the transaction is rejected by the Bitcoin network. We propose storing data in the blockchain by encoding into Bitcoin addresses. The transactions created by the proposed method are similar to the usual transactions; therefore, they will not be rejected. The proposed method expands the storage space to a maximum of N*20 bytes, thereby enabling the storage of additional information (e.g., file names, creator names, and keywords) as well as file hashes. We performed experiments with a picture and its copyright information. We set N =3, resulting in storage of 60 bytes of data. The experimental results indicate that the proposed method can timestamp a file in an average of 24 min at a possible cost of 0.24 USD. We believe that the proposed method can prove the existence and integrity of a digital file, which is helpful in copyright protection.

本誌: IEEJ Journal of Industry Applications Vol.6 No.4 （2017）

本誌掲載ページ: 252-257 p

原稿種別: 論文／英語

電子版へのリンク: https://www.jstage.jst.go.jp/article/ieejjia/6/4/6_252/_article/-char/ja/