80 The Basics of Information Security EXERCISES 1 2 3 4 5 6 7 8 9 10 What type of cipher is a Caesar cipher? What is the difference between a block and a stream cipher? ECC is classified as which type of cryptographic algorithm? What is the key point of Kerckhoffs' Principle? What is a substitution cipher? What are the main differences between symmetric and asymmetric key cryptography? Explain how 3DES differs from DES. How does public key cryptography work? Decrypt this message: V qb abg srne pbzchgref. V srne gur ynpx bs gurz. -Vfnnp Nfvzbi How is physical security important when discussing cryptographic security of data? Bibliography [1] U.S. National Security Agency, Enigma machine, U.S. National Security Agency. www.nsa. gov/about/_images/pg_hi_res/enigma_machine.jpg, 2010.