翻訳と辞書 Words near each other ・ Product (De Press album) ・ Product (mathematics) ・ Product (Sophie album) ・ Product 19 ・ Product activation ・ Product and manufacturing information ・ Product Architects, Inc. ・ Product binning ・ Product breakdown structure ・ Product bundling ・ Product category ・ Product category volume ・ Product certification ・ Product change notification ・ Product churning ・ Product cipher ・ Product classification ・ Product code ・ Product concept ・ Product control ・ Product cost management ・ Product data management ・ Product data record ・ Product defect ・ Product demonstration ・ Product description ・ Product design ・ Product design specification ・ Product detector ・ Product Development and Management Association Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Product cipher ： ウィキペディア英語版 Product cipher In cryptography, a product cipher combines two or more transformations in a manner intending that the resulting cipher is more secure than the individual components to make it resistant to cryptanalysis.〔Handbook of Applied Cryptography by Alfred J. Menezes, Paul C. van Oorschot, Scott A. Vanstone. Fifth Printing (August 2001) page 251.〕 The product cipher combines a sequence of simple transformations such as substitution, permutation, and modular arithmetic. The concept of product ciphers is due to Claude Shannon, who presented the idea in his foundational paper, ''Communication Theory of Secrecy Systems''. For transformation involving reasonable number of n message symbols, both of the foregoing cipher systems (the S-box and P-box) are by themselves wanting. Shannon suggested using a combination of S-box and P-box transformation—a product cipher. The combination could yield a cipher system more powerful than either one alone. This approach of alternatively applying substitution and permutation transformation has been used by IBM in the Lucifer cipher system, and has become the standard for national data encryption standards such as the Data Encryption Standard and the Advanced Encryption Standard. A product cipher that uses only substitutions and permutations is called a SP-network. Feistel ciphers are an important class of product ciphers. == References == 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Product cipher」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.