
CS555 Fall 2005: Cryptography
Class Information 
Class Schedule
 MW 4:305:45pm Aug 22  Dec 11, 2005, CS G066
Instructor
TA
 Jayesh Pandey
 Office: Math B3
 Email: jpandeyATcs
 Office hours: Th 10  12
Course Description
The course is an introduction to cryptography, aimed to graduate students.
Topics include:
 Concepts and principles of crypography: security services, attacks and mechanisms.
 Classical cryptographic systems: shift cipher, Vigenere and
Vernam ciphers, Jefferson wheel cipher and the Enigma machine.
 Block ciphers: DES, Blowfish, AES.
 Publickey encryption: RSA, ElGamal.
 Data integrity: hash functions, MD5, SHA1, HMAC.
 Digital signatures: RSA, ElGamal, DSA.
 Blind signatures. Group signatures.
 Authentication protocols.
 Key management: twoparty key exchange and group key management protocols.
 Applications:fair exchange, certified email, ecash.
 Notions of threshold cryptography. Proactive security.
Grade:
The grade will be based on written homework assignments (HW), two programming
projects (PP),
midterm (ME), a final exam (FE) and class participation (CP), as follows:
Grade = 20% * HW + 25% * PP + 20% * ME + 30% * FE + 5%*CP.
Exams are closed books and closed notes.
Textbooks and reading list
Textbooks
 Douglas R. Stinson, Cryptography (Theory and Practice), CRC Press 1995, ISBN: 0849385210.
 William Stallings, Cryptography and Network Security, Principles and Practice, Second Edition, Prentice Hall, 1998, ISBN: 0138690170.
Reading List:
You will also find useful:
Samuel S. Wagstaff, Cryptanalysis of Numeric Theoretic Ciphers, CRC 2000. ISBN 1584881534.
Mailing list
The class mailing list is cs555. To be added to the list sent an email
to mailer@cs.purdue.edu, with the body containing the text 'add your_email to cs555'.
Academic Integrity
Academic Honesty and Ethical behavior are required in this course,
as it is in all courses at Purdue University ( here is the
guide for academic integrity). The class will
be conducted according to the
policy
written by Professor Gene Spafford. Please take the time to read it
carefully. This will be followed unless I provide written documentation
of exceptions.
You are encouraged to talk with the professor about any questions
you have about what is permitted on any particular assignment.

Lectures 
Lecture slides will be posted below. Homework and projects will be handed in class.
This is a tentative schedule of the course.
Week 
Monday 
Wednesday 
Aug. 22, 24 
Lecture 1  Introduction to cryptography

Lecture 2  Basic ciphers  description and cryptanalysis

Aug. 29, 31 
Lecture 3  Elements of probability theory. Perfect secrecy. Entropy.

Lecture 4  Symmetric encryption. Block ciphers: DES
Homework 1 will be handed in class.

Sept. 5, 7 
No class. Labor Day.

Lecture 5  Symmetric encryption.Block ciphers:
cryptanalysis of DES, variations of DES, IDEA, RC5, Blowfish, AES

Sept. 12, 14 
Lecture 6 & 7 
Stream ciphers. RC4 and its use in WEP. Semantic security. Security of stream ciphers and block ciphers.

Lecture 8  Data integrity. Hash functions. MD5, SHA1 and RIPMD160, MACs: HMAC.
Homework 1 due in class.
Homework 2 will be handed in class.

Sept. 19. 21 
Lecture 9 and 10  Divisibility, GCD, LCM. Euclid's Algorithm for finding GCD.Prime and composite numbers.
Distribution of prime numbers. Congruence. Fermat and Euler's Theorems.

Lecture 11  RSA description and implementation.

Sept. 26, 28 
No class. Class was covered on Sept. 12.

No class. Class was covered on Sept. 19.
Homework 2 due by email to the TA, deadline is 4:30 PM.

Oct. 3. 5 
MIDTERM.

DNS Security  Dan Massey .

Oct. 10, 12 
Fall break.

Lecture 12  Midterm comment. Project 1 discusion. RSA Attacks.
Programming project 1 handed in class.

Oct. 17, 19 
Lecture 13 Semantic security and RSA. OAEP.

Lecture 14  ElGamal, DLP, CDH, DDH.

Oct. 24, 26 
Lecture 15  Security of ElGamal.

Lecture 16  Digital signatures: use of hash function, RSA, ElGamal, DSA and Schnorr.
Homework 3 handed in class.

Oct. 31, Nov. 2 
Lecture 17  Onetime digital signatures: Rabin, Merkle..
Public key infrastructure: the need for authentication, X.509
Directory Authentication Service, PGP.
Programming project 1 due on FRIDAY Nov. 4 11:59PM.

Lecture 18  Authentication protocols, entity authentication.
One time passwords, Lamport's scheme,
challengeresponse schemes, zero knowledge authentication protocols (FiatSchamir).

Nov. 7, 9 
Lecture 19  Kerberos.
Homework 3 due in class.

Lecture 20  Key establishment: NeedhamSchroeder
public key protocol, DiffieHellman, STS, MTI. IPSec
Homework 4 handed in class.

Nov. 14, 16 
Lecture 21  SSL
Project 2 handed in class.

Lecture 22  Group key management.

Nov. 21. 23 
Lecture 23  Intro to threshold cryptography.
Homework 4 due in class.

Thanksgiving.

Nov. 28, 30 
Lecture 24  Intro to secure multiparty computation.

Lecture 25  Biometrics.
Programming project 2 design document due in class. Code is due
by Friday 11:59PM

Dec. 5, 7 
Class is attending Ron Rivest talk 
Security of Voting Systems

Lecture 27  Review for the final

 

Copyright© 2005 Cristina NitaRotaru. Send your comments and questions to Cristina NitaRotaru

