Randomness and Statistical Tests

Slides:



Advertisements
Similar presentations
Kasumi Block Cipher Data Encryptors Darshan Gandhi Rushabh Pasad.
Advertisements

CS 483 – SD SECTION BY DR. DANIYAL ALGHAZZAWI (3) Information Security.
1 CIS 5371 Cryptography 5b. Pseudorandom Objects in Practice Block Ciphers.
Digital Kommunikationselektroink TNE027 Lecture 6 (Cryptography) 1 Cryptography Algorithms Symmetric and Asymmetric Cryptography Algorithms Data Stream.
Session 2: Secret key cryptography – stream ciphers – part 2.
Stream ciphers 2 Session 2. Contents PN generators with LFSRs Statistical testing of PN generator sequences Cryptanalysis of stream ciphers 2/75.
CIS 5371 Cryptography 3b. Pseudorandomness.
Introduction to CLOCK_CONTROLLED STREAM CIPHER SYSTEM Sayed Mahdi Mohammad Hasanzadeh Zaeim Electronics industries 1380.
Session 2 Symmetric ciphers 1. Stream cipher definition Recall the Vernam cipher: Plaintext Ciphertext (Running) key
1 Simulation Modeling and Analysis Pseudo-Random Numbers.
Session 2: Secret key cryptography – stream ciphers – part 1.
Computer Security CS 426 Lecture 3
Chapter 8.  Cryptography is the science of keeping information secure in terms of confidentiality and integrity.  Cryptography is also referred to as.
Block and Stream Ciphers1 Reference –Matt Bishop, Computer Security, Addison Wesley, 2003.
Practical Techniques for Searches on Encrypted Data Yongdae Kim Written by Song, Wagner, Perrig.
ETM 607 – Random Number and Random Variates
HASH Functions.
Códigos y Criptografía Francisco Rodríguez Henríquez A Short Introduction to Stream Ciphers.
Introduction to Stream Cipher Sayed Mahdi Mohammad Hasanzadeh Spring 2004.
One-Time Pad Or Vernam Cipher Sayed Mahdi Mohammad Hasanzadeh Spring 2004.
CS555Spring 2012/Topic 51 Cryptography CS 555 Topic 5: Pseudorandomness and Stream Ciphers.
Bhupendra Singh Bhupendra Singh Scientist ‘B’ Scientist ‘B’ Centre for Artificial.
The RC5 Encryption Algorithm: Two Years On Lisa Yin RC5 Encryption –Ron Rivest, December 1994 –Fast Block Cipher –Software and Hardware Implementations.
Stream Cipher Introduction Pseudorandomness LFSR Design
CS426Fall 2010/Lecture 51 Computer Security CS 426 Lecture 5 Cryptography: Cryptographic Hash Function.
@Yuan Xue CS 285 Network Security Block Cipher Principle Fall 2012 Yuan Xue.
@Yuan Xue Announcement Project Release Team forming Homework 1 will be released next Tuesday.
10.Deterministic Randomness 1.Random Sequences Random Sequences A sequence of numbers r 1, r 2,... is random if there are no discernible patterns.
RSA Laboratories’ PKCS Series - a Tutorial
Issues of Random Numbers and Cryptography
Chapter 2 Basic Encryption and Decryption
Chapter3: Block Ciphers and the Data Encryption Standard
In-Band Authentication Extension for Protocol Independent Multicast (PIM) draft-bhatia-zhang-pim-auth-extension-00 Manav Bhatia
Chapter-2 Classical Encryption Techniques.
Encryption
STRATEGIC ENCRYPTION
A cryptographically secure pseudorandom number generator for Julia
Cryptographic Hash Functions Part I
Cryptography Lecture 13.
Cryptography Lecture 19.
Chapter 7 Random Number Generation
Stream Ciphers Day 18.
Properties of Random Numbers
Introduction to Modern Symmetric-key Ciphers
STREAM CIPHERS by Jennifer Seberry.
Block Ciphers and the Data Encryption Standard (DES)
Public Key Infrastructure
Cryptography and Network Security Chapter 7
Section 2: Cryptography
Introduction to Data Structures
Cryptographic Hash Functions Part I
Cryptography Lecture 5.
Computer Simulation Techniques Generating Pseudo-Random Numbers
DISSERTATION ON CRYPTOGRAPHY.
Cryptography Lecture 9.
Homework #1 Chap. 1, 3, 4 J. H. Wang Oct. 2, 2018.
Topic 13: Message Authentication Code
Chapter -4 STREAM CIPHERS
Random Number Generation
Cryptography Lecture 14.
Hashing Hash are the auxiliary values that are used in cryptography.
Cryptography Lecture 13.
Cryptography Lecture 13.
Pseudorandom Numbers Network Security.
Hash Function Requirements
Cryptography Lecture 15.
Stream Cipher Structure
Crypto for CTFs.
By: Anthony Gervasi & Adam Dickinson
Blowfish Encryption Algorithm
Presentation transcript:

Randomness and Statistical Tests Sayed Mahdi Mohammad Hasanzadeh Hasanzadeh@Raymandcrypto.ir Spring 2004

Goals in cryptography 1) Cryptography remove the redundancy from sequence Pr(1)=Pr(0)=1/2 2) Cryptography is a mapping in the sequence space 3)Cryptography provide security in some cases: data integrity, Authentication and identification ,…

Stream Cipher Pr(Pi=0) Pr(Pi=1) 1/2 Pr(ai=0) =Pr(ai=1) =1/2 Pr(Ci=0) =Pr(Ci=1) =1/2

Generator Properties Randomness Provable security Bit rate Key length Complexity of algorithm Memory Resistant against every attack

Randomness Golomb rules Statistical tests Linear Complexity

Golomb rules Maximum period Pseudorandom 01010001101111100111 #’1’ - #’0’ =0,1 #run1=R/2^1, #run2=R/2^2,…,#runi=R/2^I t : C(t)= 01010001101111100111 #run1=5,#run2=2,#run3=2,#run4=0,#run5=1 #gap=5 , #block=5

Randomness Golomb rules Statistical tests Linear Complexity

Why Statistical tests impossible to give a mathematical proof that a generator is indeed a random bit generator, the tests help detect certain kinds of weaknesses the generator may have. This is accomplished by taking a sample output sequence of the generator and subjecting it to various statistical tests.

Statistical tests the term “accepted” should be replaced by “not rejected” six Basic Test (Using Chi-square analysis) Frequency Test: # of 0 and 1 Serial Test: # of 00, 01, 10, 11 Poker-k Test: # of each k-bit string Run Test: comparing with expected run length Autocorrelation test: correlations between s and shifted version Binary derivation

Working with a Software for Statistical Tests