|
CipherSaber is a simple symmetric encryption protocol based on the RC4 stream cipher. Its goals are both technical and political: it gives reasonably strong protection of message confidentiality, yet it's designed to be simple enough that even novice programmers can memorize the algorithm and implement it from scratch. According to the designer, a CipherSaber version in the QBASIC programming language takes just sixteen lines of code. Its political aspect is that because it's so simple, it can be reimplemented anywhere at any time, and so it provides a way for users to communicate privately even if government or other controls make distribution of normal cryptographic software completely impossible. ==History and Purpose== CipherSaber was invented by Arnold Reinhold to keep strong cryptography in the hands of the public. Many governments have implemented legal restrictions on who can use cryptography, and many more have proposed them. By publicizing details on a secure yet easy-to-program encryption algorithm, Reinhold hopes to keep encryption technology accessible to everyone. Unlike programs like PGP which are distributed as convenient-to-use prewritten software, Reinhold publishes CipherSaber only as a specification. The specification is intended to be so simple that even a beginning programmer can implement it easily. As the CipherSaber web site () explains: :''In George Lucas' ''Star Wars'' trilogy, Jedi Knights were expected to make their own light sabers. The message was clear: a warrior confronted by a powerful empire bent on totalitarian control must be self-reliant. As we face a real threat of a ban on the distribution of strong cryptography, in the United States and possibly world-wide, we should emulate the Jedi masters by learning how to build strong cryptography programs all by ourselves. If this can be done, strong cryptography will become impossible to suppress.'' The web site has a graphics file that displays as a "CipherKnight" certificate; however, that file is encrypted using CipherSaber with a known key published alongside the file. Users can view the graphic (and optionally print it out for framing) by first writing their own CipherSaber implementation to decrypt the file. By writing their own implementation and performing a few other small tasks, the user becomes a CipherKnight and the decrypted certificate attests to their knighthood. So, rather than providing a ready-made tool, CipherSaber's designer hopes to help computer users understand that they're capable of making their own strong cryptography programs without having to rely on professional developers or the permission of the government. 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「CipherSaber」の詳細全文を読む スポンサード リンク
|