Exams:

• Midterm Due Monday, Oct 25.
• Final: Wednesday Dec 15, 5:00-7:30 PM
  FINAL IS POSTED

Announcements

• Note ROOM CHANGE Memorial Building, Room 303
• You are encouraged to sign up for Csc 401, an optional practicum.
• See semester 32 homepage for an idea about this course.

Class Notes

• Introduction
• Classical ciphers
  • Substitution
  • Playfair (notes on machine reconstruction). (experiements)
  • example programs
• Machine ciphers
  • Enigma
    • Enigma description
    • Breaking Enigma
    • Cycle structure of P_iP_i+1 for a simple 6 letter enigma.
  • DES
  • mini-DES (3 round with suppressed perumutations)
  • Rijndael
• Modes of operation
  • ECB, CBC, CFB, OFB.
  • Multiple modes, multiple encipherment (3DES and DESX)
  • Authentication codes
• Stream ciphers
  • Vernum cipher and perfect secrecy.
  • Tunny and Fish
  • RC4
• Computational security
  • Probabilistic computation
  • Classes RP, ZPP, BPP
  • Models of security
  • Hash functions
  • Psuedorandom generators
• Public-key cryptography, RSA
  • Mathematical background
  • RSA, Security of RSA
  • Miller-Rabin probabilistic primality tests, factoring.
  • OAEP, PPS
• Public-key cryptography, El Gamal
  • DL assumption
  • Generators
  • Chinese Remainder Theorem
  • Pohlig-Hellman Algorithm
  • Second-bit security
  • DSA
• Authentication and key establishment
  • Indirect: kerberos
  • Password, challenge-response.
  • Public-key/signature based
  • Zero-knowledge identification
• Commitment
  • Hiding and Binding properties, unconditional or computational
  • Flipping a coing by telephone
• Digital Elections,
  • Secret Sharing
  • Threshold cryptography
  • Proof of Knowledge
  • Honest Verifier PoK
  • Non-interactive PoK
• Digital Cash
• Secure Multiparty Computation
  • Simple demonstration of ZK with a deck of cards.
  • Ben-Or, Goldwasser, Wigderson solution.
  • Using Oblivious Transfer

Homework

• See NOVA program Decoding Nazi Secrets. Solve the Cipher (note: Shockwave plugin required.)
  Send me the signer's name as proof of success.
• Breaking Bad Ciphers. Due: 13 September 2004
• Chap. 2, Ex. 1 and 2.
  Due: Oct 1.
• Read 9.1 in class text, look over 9.2. Do exercise 1, chapter 9.
  Due: Oct 4.
• Exercises 1, 2 and 3, chapter 4.
  Due: Nov 22.

References

• Enigma, Wladyslaw Kozaczuk. Articles on reconstruction and breaking of Enigma by Polish mathematicians prior to WWII.
• Breaking Tunny by Tutte. Article on reconstructing the masking sequence for encryption of German High Command network.
• John Savard's page on machine ciphers.
• Biham, Eli, Cryptanalysis of multiple modes of operation , J. Cryptology 11:1 (1998) 45-58.
• Biham, Eli, Cryptanalysis of triple modes of operation, J. Cryptology 12:3 (1999) 161-184.
• Cramer, Gennaro, Schoenmakers, A secure and optimally efficient mutli-authority election scheme, Eurocrypt 97.
• Jens Groth, Extracting witnesses from proofs of knowledge in the random oracle model
• Cramer, Damgard, Schoenmakers, Proofs of partial knowledge and simplified design of witness hiding protocosl, Crypto 94
• Michael Ben-Or, Shafi Goldwasser, Avi Wigderson, Completeness theorems for non-cryptographic fault-tolerant distributed computation, Proc. 20-th ACM Symposium on Theory of Computing, 1988. pp 1-10.
• John Milne, Elliptic Curves

SliceOfLife

• Helger Lipmaa Notes
• mersenne.org, and Prime network
• Van Eck radiation (security, not crypto, but an enjoyable group of pages anyway.)