CSCE 477/877 Cryptography and Computer Security
November 18, 2015
Homework 4
DUE: December 2 (Wednesday), 2015 at 1:30pm
Name_
CSE Login_
Instructions: Follow instructions carefully, failure to do so
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 3: Block Cipher Modes of Operation
Modes of Encryption
Encrypting Long Texts
So far we have a block cipher, which
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 6: Digital Signatures and Authentication
Discrete Logarithms
Discrete Logarithms
Given , , p, p is a prime, and are no
CSCE 477/877: Cryptography and
Computer Security
Exam 1
Exam data: Sep. 21, 2015 (Monday)
Time: 1:30pm~2:20pm (in class)
It is close note, close book examination.
Calculator and a one-page aid sheet a
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 5: RSA
1
Review: Number Theory
Modular arithmetic
GF(p)
Relatively Prime: no common factors other than 1
Finding multi
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 4: Basic Number Theory
1
Review: AES
Key size: 128-, 192-, or 256-bits.
Block size: 128 bits
Number of rounds:
AES 12
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 7: Hash Functions
1
Review: Discrete Logarithm
Compute discrete logarithm is hard.
x (mod p)
Given ,p, to compute x
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Opera&ng System Security
1
Announcement
Exam 2: Nov. 23 (Monday) in class
close book, close note, 4 q
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Malware
11/14/15
Malware
1
Viruses, Worms, Trojans, Rootkits
Malware can be classied into several cat
CSCE477/877
Cryptography and
Computer Security
Buer Overow A?acks
LimitaCons of Unix Permissions
Unix permissions are not perfect
Groups are restricCve
LimitaCo
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 8: Key Management
1
Review: Hash Functions
Hash functions take arbitrarily long input and generate fixedlength output
CS3235
Introduction to Computer Security
Hugh Anderson
19th November 2003
Preface
The ofcial line:
With the widespread use of computers and Internet as well as electronic commerce,
computer security b
CSCE 477/877 Cryptography and
Computer Security
Final Exam Preparation Guide
Exam date: Dec. 14, 2015 (Monday) Time: 1:00pm~3:50pm
1. The exam will be close book, close note, 110-minutes examination.
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Web Security
12/2/15
Web Security
1
Announcement
Project Presenta8on Next Week
HW4 Due: December 2 (1
CSCE 477/877 Cryptography and Computer Security
Project Topic List
You can select topics from the following list or you may come up with
your own topic.
- Research project examples:
Android security,
CSCE 477/877: Cryptography and Computer
Security
Homework 1 Solution
1.
2.
3.
4.
5.
6.
(1). Shift Cipher: (using frequency analysis)
Plaintext:
There was nothing so VERY remarkable in that nor did Ali
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 6: Digital Signatures and Authentication
Review: RSA
RSA
Key generation: public key (e, n), private key (d)
Encry
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 5: RSA
1
Review: Number Theory
Modular arithmetic
GF(p)
Relatively Prime: no common factors other than 1
Finding mu
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 3: AES and Modes of Operation
Review
Three types of cryptography
Security uses
Secret key cryptography
Public key cryp
CSCE 477/877 Cryptography & Computer Security (Fall 2017)
Syllabus
Instructor:
Class Time:
Location:
Office:
Office Hours:
Email:
Web Page:
TA:
Dr. Qiben Yan
M, W, F 9:30 AM - 10:20 AM
110 Avery Hall
CSCE 477/877 Cryptography and Computer Security
Homework 1 Solution
Total: 100 points
1. (a): The plaintext is GREAT NEWS
(b) a needs to be relatively prime with 26. As the decryption function is a^-1
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 4: Basic Number Theory
1
Review: AES
Key size: 128-, 192-, or 256-bits.
Block size: 128 bits
Number of rounds:
AES 12
CSCE 477/877: Cryptography and
Computer Security
Mid-Term Exam (Sample)
It is open note, open book examination. Calculator is allowed.
No Internet access is allowed.
You have 60 minutes to complete al
CSCE 477/877
Cryptography and Computer Security
Instructor:
Dr. Qiben Yan
Lecture 2: Symmetric Cryptography and DES
Review
Classical cryptosystems
Shift cipher
Affine cipher
General substitutio