Abstract

In recent years, several new attacks on DES were introduced. These attacks have led researchers to suggest stronger replacements for DES, and in particular new modes of operation for DES. The most popular new modes are triple DES variants, which are claimed to be as secure as triple DES. To speed up hardware implementations of these modes, and to increase the avalanche, many suggestions apply several standard modes sequentially. In this paper we study these multiple (cascade) modes of operation. This study shows that many multiple modes are much weaker than multiple DES, and their strength is comparable to a single DES.We conjecture that operation modes should be designed around an underlying cryptosystem without any attempt to use intermediate data as feedback, or to mix the feedback into an intermediate round. Thus, in particular, triple DES used in CBC mode is more secure than three single DES's used in triple CBC mode. Alternatively, if several encryptions are applied to each block, the best choice is to concatenate them to one long encryption, and build the mode of operation around it.KeywordsMultiple ModeData Encryption StandardLinear CryptanalysisDifferential CryptanalysisPlaintext AttackThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.