Introduction to cryptography

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Cryptography: An Introduction (3rd Edition) Nigel Smart Preface To Third Edition The third edition contains a number of new chapters, and vari ous material has been moved around. •The chapter on Stream Ciphers has been split into two. One cha pter now deals with the general background and historical matters, the second c hapter deals with modern constructions based on LFSR’s. The reason for this is to acco modate a major new section on the Lorenz cipher and how it was broken. This compliments t he earlier section on the breaking of the Enigma machine. I have also added a brief disc ussion of the A5/1 cipher, and added some more diagrams to the discussion on modern stre am ciphers. •I have added CTR mode into the discussion on modes of operatio n for block ciphers. This is because CTR mode is becoming more used, both by itself and a s part of more complex modes which perform full authenticated encryption. Thus it is important that students are exposed to this mode. •I have reordered various chapters and introduced a new part o n protocols, in which we cover secret sharing, oblvious transfer and multi-party co mputation. This compliments the topics from the previous edition of commitment schemes and z ero-knowledge protocols, which are retained a moved around a bit. Thus the second editi on’s Part 3 has now been split into two parts, the material on zero-knowledge proofs has now been moved to Part 5 and this has been extended to include other topics, such as ob livious transfer and secure multi-party computation. •The new chapter on secret sharing contains a complete descri ption of how to recombine shares in the Shamir secret-sharing method in the presence o f malicious adversaries. To our knowledge this is not presented in any other elementary t extbook, although it…