CS 178 Introduction to Cryptography
Winter Term 2020
Department of Computer Science
University of California Santa Barbara
- Instructor: Professor Koç
→ Koç is pronounced as "Coach"
- Class Schedule: Monday, Wednesday 2:00-3:15pm
- Classroom: Girvetz 2128
- Instructor's Office hours: Tue 4:00-5:30pm
- Instructor's Office: Phelps 1408 (Koç Lab -
- The TAs are
Kalyan Garapaty - firstname.lastname@example.org
Suriya Dakshina Murthy - email@example.com
- TA Office Hours are
Tuesday 2:00-4:00pm Suriya
Thursday 12:00-2:00pm Kalyan
- TA Office: Trailer 936
- Discussion Schedule and Room:
Thursday 2:00-2:50pm; Trailer 387 1015 (Kalyan)
Thursday 3:00-3:50pm; Trailer 387 1011 (Suriya)
- Please join the cs178
page for class discussions.
- Check the class website, the Piazza page, and/or your email once a day.
- Course material is in the folder docx
- The grades:
Code = 2047*StudentPerm mod 9973
There will be 5 homework assignments during the term, and
they are to be uploaded via Dropbox. The links will be
provided. Submit your homework assignment as a single PDF file.
You may also handwrite and submit a scanned image (as a single PDF).
Do not submit unreadable, poor phone camera images; if you do,
we will not grade them and your grade will be 0.
No late homework is accepted. ←
- Homework Assignment 1: (due 5pm on Monday Jan 20)
From the Rubinstein book, answer the
(Page 7: 2.4 Problems) 2, 4, 6
(Page 52: 5.6 Problems) 1, 5
(Page 62: 6.4 Problems) 1, 2
- Homework Assignment 2: hw2.pdf
- due 5pm on Monday Feb 3
- Homework Assignment 3: hw3.pdf
- due 11pm on Saturday Feb 15 ←
- Homework Assignment 4: hw4.pdf
- due 11pm on Saturday Feb 29 ←
- Homework Assignment 5: hw5.pdf
- due 11pm on Saturday Mar 14 ←
Midterm and Final Exams
The Midterm exam date: Wednesday Feb 26
The Take-Home Final exam is here:
The deadline for submission is
10pm on Monday March 16.
Link for submission: is closed now
Weekly Course Plan
- Week 01:
Cryptography, cryptanalysis, cryptology
- Week 02:
Classical ciphers, Shift, Affine, Hill, Vigenere,
Affine Block Ciphers
- Week 03:
Number theory, stream ciphers, one-time pad, Vernam, RNGs
- Week 04:
LCGs, LFSRs, and CAs
- Week 05:
DES, perfect secrecy, basic modes of operation, 3DES,
- Week 06:
Groups, finite fields, AES, advanced modes;
- Week 07:
- Week 08:
Factoring, primality testing, discrete logs, Diffie-Hellman
- Week 09:
Hash functions and digital signatures
- Week 10:
Rijndael Animator & Inspector
Crypto Journals and Archives
Useful Crypto Links
This is an introductory course on methods, algorithms, techniques,
and tools of cryptography. We study in detail algorithmic and
mathematical aspects of cryptographic methods and protocols, such as
secret-key cryptography, public-key cryptography, hash functions, and
digital signatures. We show how these techniques are used to solve
particular data and communication security problems. This course
material is useful for computer science, electrical engineering, and
mathematics students who are interested in learning how cryptographic
algorithms and methods are embedded in information systems, providing
confidentiality, integrity, non-repudiation, and authenticity of stored
and transmitted digital data.
- Secret-Key Cryptography: Symmetric and asymmetric systems; cryptanalysis;
alphabets and words; permutations; block ciphers; stream ciphers;
matrices and linear maps; Vigenere, Hill and permutation ciphers;
perfect secrecy; birthday paradox; Vernam cipher and one-time pad;
deterministic and true random numbers; DES and AES.
- Mathematical Background: Integers; cost of arithmetic operations;
gcd and extended gcd computation; Euclidean algorithm; factoring into
primes; modular arithmetic; groups, rings, and fields; orders of elements,
groups and subgroups; exponentiaton; Chinese remainder theorem;
polynomials and finite fields.
- Public-Key Cryptography: RSA algorithm, Rabin's algorithm,
Diffie-Hellman key exchange, ElGamal; Factoring and generating
prime numbers, Fermat test, Miller-Rabin test; Discrete logarithms,
Pollar rho algorithm, index calculus.
- Hash Functions: Fundamentals, one-way functions, preimage
and second preimage computations, compression functions, MD5,
SHA-1, an SHA-2 and SHA-3 family; Message authentication functions.
- Digital Signatures: RSA, ElGamal, DSA, ECDSA, special signatures.
- Advanced Topics: Elliptic curve cryptography, secret sharing,
one-time passwords, challenge-response protocols, certificates.
- Simon Rubinstein-Salzedo.
Cryptography, Springer, 2018.
- Available without cost to UCSB students:
- Homework Assignments: 30 %
- Midterm Exam: 30 %
- Final Exam: 40 %
An introduction to the basic concepts and techniques of cryptography
and cryptanalysis. Topics include: The Shannon theory, classical systems,
the enigma machine, the data encryption standard, public key systems,
digital signatures, file security.
CS 10 or CS 24; CS 40; PSTAT 120A or PSTAT 121A or ECE 139
or permission of instructor.
This class is open to all undergraduate CS, ECE, and MATH students,
with appropriate discrete mathematics background.
Academic Integrity ←
Çetin Kaya Koç