- What advantages do transposition ciphers offer over substitution ciphers? What advantages do substitution ciphers offer over transposition ciphers?
- Many of the examples of cryptography in this chapter dealt with uses in political or military contexts, where the need for keeping secrets is usually clear. What are some reasons that people today might need cryptography in other settings?
- On page 15, Singh writes, “Cryptanalysis could not be invented until a civilization had reached a sufficiently sophisticated level of scholarship in several disciplines, including mathematics, statistics, and linguistics.” If such a level of scholarship was required for the development of the frequency analysis approach to solving substitution ciphers, what do you make of the fact that amateur cryptanalysts today often use that approach “on their own,” so to speak, without being trained in it?
- On page 41, Singh writes, “The cipher of Mary Queen of Scots clearly demonstrates that a weak encryption can be worse than no encryption at all.” What does Singh mean by this and what does it imply for those who would attempt to keep their communications secret through cryptography?
As a reminder, note that responding to these questions by leaving a comment here on the blog is one of the ways in which you can contribute to your participation grade in this course.