Jan 17

Lecture Introduction. Private-key cryptography. The syntax of private-key encryption. Historical ciphers and Their Cryptanalysis.: KL 1.1-1.3

Jan 22

Lecture Principles of Modern Cryptography. Modern cryptography: definitions, assumptions, and proofs. Defining Perfectly Secure Encryption.: KL 1.4 and 2.1

Discussion Discussion 1: Solution

Jan 23

Homework Homework 1: LaTeX, Solution

Jan 24

Lecture Game-Based Definition for Encryption. The one-time pad. Limitations of perfect secrecy. A computational notion of security.: KL 2.2-2.3, 3.1, and 3.2.1

Jan 29

Lecture Pseudorandomness. The pseudo-OTP. Proofs by reduction, and a proof of security for the pseudo-OTP.: KL 3.3

Discussion Discussion 2: Solution

Jan 30

Homework Homework 2: Q3 Starter Code, LaTeX, Note On Negligible Functions, Solution

Jan 31

Lecture Security for multiple encryptions. Drawbacks of deterministic encryption. Chosen-plaintext attacks and CPA-security. Pseudorandom Functions. CPA Secure Encryption from Pseudorandom Functions: KL 3.4 and 3.5

Feb 5

Lecture Encryption from stream ciphers and block ciphers. Chosen-Ciphertext Attacks. Hybrid Arguments.: KL 3.6 and 3.7

Discussion Discussion 3: Solution

Feb 6

Homework Homework 3: LaTeX, Solution

Feb 7

Lecture Practical constructions of stream ciphers. Substitution-permutation networks: KL 6.1 and 6.2.1

Feb 12

Lecture Practical constructions of block ciphers. Substitution-permutation networks (SPNs). Fiestel Networks. The data encryption standard (DES).: KL 6.2.1, 6.2.2, 6.2.3, and 6.2.4.

Discussion Discussion 4: Solution

Feb 14

Midterm Midterm I: Solution

Feb 19

No Class (President’s Day)

Discussion Discussion 5 (reviewed midterm 1): Midterm 1 Solution

Feb 20

Homework Homework 4: LaTeX, Solution

Feb 21

Lecture Message integrity and message authentication codes (MACs). Defining security for MACs. Constructing MACs.: KL 4.1, 4.2, 4.3 and 4.4.1

Feb 26

Lecture Authenticated encryption and CCA-security.: KL 4.5.1, and 4.5.2 (no proof), 4.5.3, 4.5.4

Discussion Discussion 6: Solution

Feb 27

Homework Homework 5: LaTeX, Solution

Feb 28

Lecture Hash functions and collision resistance. Birthday attacks on hash functions. Additional applications of hash functions.: KL 5.1.1, 5.2, 5.3.1, 5.4.1, and 5.6.1-5.6.3

Mar 4

Lecture One-Way Functions and Implications: KL 7.1, 7.2, 7.3.1, 7.4, 7.5, and 7.7

Discussion Discussion 7: Solution

Mar 5

Homework Homework 6: LaTeX, Solution

Mar 6

Lecture Groups. Hardness assumptions in cyclic groups: the discrete-logarithm assumption and Diffie-Hellman problems. Hash Functions Construction. The Diffie-Hellman key-exchange protocol.: KL 8.1.1-8.1.2 (self-study), 8.1.3, 8.3.1-8.3.3, 8.4.2, and 10

Mar 11

Lecture Public-key encryption: syntax and definitions of security. El Gamal encryption. Definitions of security for public-key encryption.: KL 11.1 11.2, 11.4.1, and 11.4.4 (only the discussion that El Gamal encryption is malleable).

Discussion Discussion 8: Solution

Mar 12

Homework Homework 7: LaTeX, Solution

Mar 13

Lecture Hybrid encryption and the KEM/DEM paradigm. El Gamal encryption. Composite Order Groups. RSA Encryption: 11.3 (skip proof of Theorem 11.12), 11.4.2, and 11.5.1

Mar 15

Midterm Review Session: Slides, Recording

Mar 18

Lecture Review for Midterm II

Mar 20

Midterm Midterm II: Solution, Example Answers

Mar 25: Spring Break
Mar 27: Spring Break

Apr 1

Lecture Digital signatures. The hash-and-sign paradigm. Schnorr Signature Scheme. Certificates and public-key infrastructures.: KL 12.1-12.3, 12.5.1 and 12.7

Discussion Discussion 9: Solution

Apr 2

Homework Homework 8: LaTeX, Solution

Apr 3

Lecture Pairings, Identity Based Encryption, CCA Secure Public-Key Encryption: Boneh & Shoup, Chapter 15

Apr 8

Lecture Commitment Schemes: Special Topics

Discussion Discussion 10: Solution

Apr 9

Homework Homework 9: Q3 Starter Code, LaTeX, Solution

Apr 10

Lecture Zero-Knowledge Proofs: Supplemental Materials

Apr 15

Lecture Zero-Knowledge Proofs: Supplemental Materials

Discussion Discussion 11: Solution

Apr 17

Homework Homework 10: LaTeX, Solution

Apr 17

Lecture Succinct Proofs: Special Topics

Apr 22

Lecture Secret Sharing: Special Topics

Discussion Discussion 12: Solution

Apr 24

Lecture Multiparty computation and review for final exam: Special Topics

May 7

Final Exam Exam: Solution

Welcome to CS 171!

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Week 4

Week 5

Week 6

Week 7

Week 8

Week 9

Week 10

Week 11

Week 12

Week 13

Week 14

Week 15

Week 17