4 ms·

How does content of this compares to e.g. newer (still 30 year old) book like Applied Cryptography by Schneier? I understand these PDFs are even more "applied"

• elahieh 5y ago
  This book, like the MILCRYP series, is focussed on cryptanalysis of "classical" (pre-computer) ciphers. The "Principles of Cryptodiagnosis" chapter (which I think is the most interesting "reveal") is an update of the author's 1970 monograph "Ars Conjectandi". Around 1976/1977 when the book came out, the stronger "modern" cryptography was becoming public - DES, public key crypto, Diffie-Hellman key exchange, the paper "New Directions in Cryptography" etc. The Schneier book is all about those - e.g. DES, RSA, GOST etc and applying known systems. It's not about cryptanalysis of pre-computer "classical systems" - at the start he says "This is not a book about classical cryptography". There's a brief note mentioning that "double transposition" is a very strong classical system, and that's about it.
  • schoen 5y ago
    Also, Schneier is trying to teach people how to implement cryptosystems, not how to break them or how to design them (which you allude to by saying "applying known systems"). One difference between classical and modern cryptography is that classical cryptography usually works at the letter or character level, while modern cryptography usually treats plaintexts and ciphertexts as uninterpreted sequences of bits and uses bit-level operations. Sometimes these two perspectives have equivalences or similarities, but mostly not if you're looking at stuff like block cipher S-boxes or block cipher modes of operation or Merkle-Damgård hash functions or whatever.
  • comboy 5y ago
    Thanks!