dc.contributor.author Thorsen, Ole Rydland eng dc.date.accessioned 2014-02-10T12:58:04Z dc.date.available 2014-02-10T12:58:04Z dc.date.issued 2013-12-10 eng dc.date.submitted 2013-12-10 eng dc.identifier.uri https://hdl.handle.net/1956/7779 dc.description.abstract In this thesis, we will study a new stream cipher, Grein, and a new cryptoprimitive used in this cipher. The second chapter gives a brief introduction to cryptography in general. The third chapter looks at stream ciphers in general, and explains the advantages and disadvantages of stream ciphers compared to block ciphers. In the fourth chapter the most important building blocks used in stream ciphers are explained. The reader is excepted to know elementary abstract algebra, as much of the results in this chapter depend on it. In the fifth chapter, the stream cipher Grain is introduced. In chapter six, the new stream cipher, Grein, is introduced. Here, we look at the different components used in the cipher, and how they operate together. In chapter seven, we introduce an alteration to the Grein cryptosystem, which hopefully have some advantages en_US dc.format.extent 603354 bytes eng dc.format.mimetype application/pdf eng dc.language.iso eng eng dc.publisher The University of Bergen en_US dc.subject LFSR dc.subject NFSR dc.subject de Bruijn Sequence dc.subject Stream ciphers eng dc.subject Cryptography eng dc.title Grein. A New Non-Linear Cryptoprimitive en_US dc.type Master thesis dc.rights.holder Copyright the author. All rights reserved en_US dc.description.degree Master i Informatikk en_US dc.description.localcode MAMN-INF dc.description.localcode INF399 dc.subject.nus 754199 eng fs.subjectcode INF399
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