Decrypted Secrets: Methods and Maxims of Cryptology

Indeholder "Preface", "Part I: Cryptography - The People", " 1. Introductory Synopsis", " 1.1 Cryptography and Steganography", " 1.2 Semagrams", " 1.3 Open Code: Masking", " 1.4 Cues", " 1.5 Open Code: Veiling by Nulls", " 1.6 Open Code: Veiling by Grilles", " 1.7 Classification of Cryptographic Methods", " 2. Aims and Methods of Cryptography", " 2.1 The Nature of Cryptography", " 2.2 Encryption", " 2.3 Cryptosystems", " 2.4 Polyphony", " 2.5 Character Sets", " 2.6 Keys", " 3. Encryption Steps: Simple Substitution", " 3.1 Case V(1) --> W (Unipartite Simple Substitutions)", " 3.2 Special Case V <--> V (Permutations)", " 3.3 Case V(1) --> W^m (Multipartite Simple Substitutions)", " 3.4 The General Case V(1) --> W(m), Straddling", " 4. show more Encryption Steps: Polygraphic Substitution and Coding", " 4.1 Case V(2) --> W(m), (Digraphic Substitutions)", " 4.2 Special Cases of Playfair and Delastelle: Tomographic Methods", " 4.3 Case V(3) --> W(m), (Trigraphic Substitutions)", " 4.4 The General Case V(n) --> W(m) : Codes", " 5. Encryption Steps: Linear Substitution", " 5.1 Self-reciprocal Linear Substitutions", " 5.2 Homogeneous Linear Substitutions", " 5.3 Binary Linear Substitutions", " 5.4 General Linear Substitutions", " 5.5 Decomposed Linear Substitutions", " 5.6 Decimated Alphabets", " 5.7 Linear Substitutions with Decimal and Binary Numbers", " 6. Encryption Steps: Transposition", " 6.1 Simplest Methods", " 6.2 Columnar Transpositions", " 6.3 Anagrams", " 7. Polyalphabetic Encryption: Families of Alphabets", " 7.1 Iterated Substitutions", " 7.2 Cyclically Shifted and Rotated Alphabets", " 7.3 Rotor Crypto Machines", " 7.4 Shifted Standard Alphabets: Vigenère and Beaufort", " 7.5 Unrelated Alphabets", " 8. Polyalphabetic Encryption: Keys", " 8.1 Early Methods with Periodic Keys", " 8.2 'Double Key'", " 8.3 Vernam Encryption", " 8.4 Quasi-nonperiodic Keys", " 8.5 Machines that Generate Their Own Key Sequences", " 8.6 Off-Line Forming of Key Sequences", " 8.7 Nonperiodic Keys", " 8.8 Individual, One-Time Keys", " 8.9 Key Negotiation and Key Management", " 9. Composition of Classes of Methods", " 9.1 Group Property", " 9.2 Superencryption", " 9.3 Similarity of Encryption Methods", " 9.4 Shannon's 'Pastry Dough Mixing'", " 9.5 Confusion and Diffusion by Arithmetical Operations", " 9.6 DES and IDEA(R)", " 10. Open Encryption Key Systems", " 10.1 Symmetric and Asymmetric Encryption Methods", " 10.2 One-Way Functions", " 10.3 RSA Method", " 10.4 Cryptanalytic Attack upon RSA", " 10.5 Secrecy Versus Authentication", " 10.6 Security of Public Key Systems", " 11. Encryption Security", " 11.1 Cryptographic Faults", " 11.2 Maxims of Cryptology", " 11.3 Shannon's Yardsticks", " 11.4 Cryptology and Human Rights", "Part II: Cryptanalysis - The Machinery", " 12. Exhausting Combinatorial Complexity", " 12.1 Monoalphabetic Simple Encryptions", " 12.2 Monoalphabetic Polygraphic Encryptions", " 12.3 Polyalphabetic Encryptions", " 12.4 General Remarks on Combinatorial Complexity", " 12.5 Cryptanalysis by Exhaustion", " 12.6 Unicity Distance", " 12.7 Practical Execution of Exhaustion", " 12.8 Mechanizing the Exhaustion", " 13. Anatomy of Language: Patterns", " 13.1 Invariance of Repetition Patterns", " 13.2 Exclusion of Encryption Methods", " 13.3 Pattern Finding", " 13.4 Finding of Polygraphic Patterns", " 13.5 The Method of the Probable Word", " 13.6 Automatic Exhaustion of the Instantiations of a Pattern", " 13.7 Pangrams", " 14. Polyalphabetic Case: Probable Words", " 14.1 Non-Coincidence Exhaustion of Probable Word Position", " 14.2 Binary Non-Coincidence Exhaustion", " 14.3 The De Viaris Attack", " 14.4 Zig-Zag Exhaustion of Probable Word Position", " 14.5 The Method of Isomorphs", " 14.6 A clever brute force method: EINSing", " 14.7 Covert Plaintext-Cryptotext Compromise", " 15. Anatomy of Language: Frequencies", " 15.1 Exclusion of Encryption Methods", " 15.2 Invariance of Partitions", " 15.3 Intuitive Method: Frequency Profile", " 15.4 Frequency Ordering", " 15.5 Cliques and Matching of Partitions", " 15.6 Optimal Matching", " 15.7 Frequency of Multigrams", " 15.8 The Combined Method of Frequency Matching", " 15.9 Frequency Matching for Polygraphic Substitutions", " 15.10 Free-Style Methods", " 15.11 Unicity Distance Revisited", " 16. Kappa and Chi", " 16.1 Definition and Invariance of Kappa", " 16.2 Definition and Invariance of Chi", " 16.3 The Kappa-Chi Theorem", " 16.4 The Kappa-Phi Theorem", " 16.5 Symmetric Functions of Character Frequencies", " 17. Periodicity Examination", " 17.1 The Kappa Test of Friedman", " 17.2 Kappa Test for Multigrams", " 17.3 Cryptanalysis by Machines: Searching for a period", " 17.4 Kasiski Examination", " 17.5 Building a Depth and Phi Test of Kullback", " 17.6 Estimating the Period Length", " 18. Alignment of Accompanying Alphabets", " 18.1 Matching the Profile", " 18.2 Aligning Against Known Alphabet", " 18.3 Chi Test: Mutual Alignment of Accompanying Alphabets", " 18.4 Reconstruction of the Primary Alphabet", " 18.5 Kerckhoffs' Symmetry of Position", " 18.6 Stripping off Superencryption: Difference Method", " 18.7 Decryption of Code", " 18.8 Reconstruction of the Password", " 19. Compromises", " 19.1 Kerckhoffs' Superimposition", " 19.2 Superimposition for Encryptions with a Key Group", " 19.3 COLOSSUS", " 19.4 Adjustment 'in depth' of Messages", " 19.5 Cryptotext-Cryptotext Compromises", " 19.6 Cryptotext-Cryptotext Compromise: ENIGMA Indicator Doubling", " 19.7 Plaintext-Cryptotext Compromise: Feedback Cycle", " 20. Linear Basis Analysis", " 20.1 Reduction of Linear Polygraphic Substitutions", " 20.2 Reconstruction of the Key", " 20.3 Reconstruction of a Linear Shift Register", " 21. Anagramming", " 21.1 Transposition", " 21.2 Double Columnar Transposition", " 21.3 Multiple Anagramming", " 22. Concluding Remarks", " 22.1 Success in Breaking", " 22.2 Mode of Operation of the Unauthorized Decryptor", " 22.3 Illusory Security", " 22.4 Importance of Cryptology", "Appendix: Axiomatic Information Theory", "Bibliography", "Index", "Photo Credits", "List of Color Plates", " Plate A. The disk of Phaistos", " Plate B. Brass cipher disks", " Plate C. The 'Cryptograph' of Wheatstone", " Plate D. The US Army cylinder device M-94", " Plate E. The US strip device M-138-T4", " Plate F. The cipher machine of Kryha", " Plate G. The Hagelin 'Cryptographer' C-36", " Plate H. The US Army M-209, Hagelin licensed", " Plate I. The cipher machine ENIGMA with four rotors", " Plate K. Rotors of the ENIGMA", " Plate L. The British rotor machine TYPEX", " Plate M. Uhr box of the German Wehrmacht", " Plate N. Cipher teletype machine Lorenz SZ 42", " Plate O. Russian one-time pad", " Plate P. Modern crypto board", " Plate Q. CRAY Supercomputers".

Glimrende gennemgang af et hav af krypteringsmetoder og hvordan man kan knække dem. Der er en særlig sød teknik med at strække og folde et billede i afsnit 9.3. show less