Block Ciphers and the Data Encryption Standard (DES) Modified by: Dr. Ramzi Saifan
|
|
|
- Sherilyn Jacobs
- 5 years ago
- Views:
Transcription
1 Block Ciphers and the Data Encryption Standard (DES) Modified by: Dr. Ramzi Saifan
2 Block ciphers Keyed, invertible Large key space, large block size A block of plaintext is treated as a whole and used to produce a ciphertext block of equal length Typically a block size of 64 or 128 bits is used The majority of network-based symmetric cryptographic applications make use of block ciphers
3 Data Encryption Standard (DES) Developed in 1970s by IBM / NSA / NBS Non-public design process Block size = 64-bit input/output Key size = 56 bits out of a 64 bits One bit in each octet is a parity-check bit Was the most widely used encryption scheme until the introduction of the Advanced Encryption Standard (AES) in 2001
4 Feistel Cipher Proposed the use of a cipher that alternates substitutions and permutations Substitutions Permutation Each plaintext element or group of elements is uniquely replaced by a corresponding ciphertext element or group of elements No elements are added or deleted or replaced in the sequence, rather the order in which the elements appear in the sequence is changed Is the structure used by many significant symmetric block ciphers currently in use.
5 Feistel Cipher Structure
6 Feistel Cipher Design Features Block size Larger block sizes mean greater security but reduced encryption/decryption speed for a given algorithm Key size Larger key size means greater security but may decrease encryption/decryption speeds Number of rounds The essence of the Feistel cipher is that a single round offers inadequate security but that multiple rounds offer increasing security Subkey generation algorithm Greater complexity in this algorithm should lead to greater difficulty of cryptanalysis Round function F Greater complexity generally means greater resistance to cryptanalysis Fast software encryption/decryption In many cases, encrypting is embedded in applications or utility functions in such a way as to preclude a hardware implementation; accordingly, the speed of execution of the algorithm becomes a concern Ease of analysis If the algorithm can be concisely and clearly explained, it is easier to analyze that algorithm for cryptanalytic vulnerabilities and therefore develop a higher level of assurance as to its strength
7 Feistel Example
8 DES Encryption Algorithm
9 Round Function
10 Average Time Required for Exhaustive Key Search
11 Block Cipher Design Principles: Design of Function F The heart of a Feistel block cipher is the function F The more nonlinear F, the more difficult any type of cryptanalysis will be The SAC and BIC criteria appear to strengthen the effectiveness of the confusion function The algorithm should have good avalanche properties Strict avalanche criterion (SAC) States that any output bit j should change with probability 1/2 when any single input bit i is inverted for all i, j Bit independence criterion (BIC) States that output bits j and k should change independently when any single input bit i is inverted for all i, j, and k
12 Concerns about DES Short key length DES cracker, can break DES in days Computation can be distributed to make it faster Does not mean DES is insecure ; depends on desired security Short block length Repeated blocks happen too frequently Some (theoretical) attacks have been found Claimed known to DES designers 15 years before public discovery!
13 Double DES
14 Meet-in-the-Middle Attack The use of double DES results in a mapping that is not equivalent to a single DES encryption The meet-in-the-middle attack algorithm will attack this scheme and does not depend on any particular property of DES but will work against any block encryption cipher
15 Triple-DES with Two-Keys Obvious counter to the meet-in-the-middle attack is to use three stages of encryption with three different keys This raises the cost of the meet-in-the-middle attack to 2 112, which is beyond what is practical Has the drawback of requiring a key length of 56 x 3 = 168 bits, which may be somewhat unwieldy As an alternative Tuchman proposed a triple encryption method that uses only two keys 3DES with two keys is a relatively popular alternative to DES and has been adopted for use in the key management standards ANSI X9.17 and ISO 8732
16 Multiple Encryption
17 Triple DES with Three Keys Many researchers now feel that three-key 3DES is the preferred alternative Three-key 3DES has an effective key length of 168 bits and is defined as: C = E( K 3, D( K 2, E( K 1, P))) Backward compatibility with DES is provided by putting: K 3 = K 2 or K 1 = K 2 A number of Internet-based applications have adopted three-key 3DES including PGP and S/MIME
18 Next is AES
19
Cryptography and Network Security. Sixth Edition by William Stallings
Cryptography and Network Security Sixth Edition by William Stallings Chapter 3 Block Ciphers and the Data Encryption Standard All the afternoon Mungo had been working on Stern's code, principally with
Block Ciphers and Data Encryption Standard. CSS Security and Cryptography
Block Ciphers and Data Encryption Standard CSS 322 - Security and Cryptography Contents Block Cipher Principles Feistel Structure for Block Ciphers DES Simplified DES Real DES DES Design Issues CSS 322
Introduction to Network Security Missouri S&T University CPE 5420 Data Encryption Standard
Introduction to Network Security Missouri S&T University CPE 5420 Data Encryption Standard Egemen K. Çetinkaya Egemen K. Çetinkaya Department of Electrical & Computer Engineering Missouri University of
Chapter 3 Block Ciphers and the Data Encryption Standard
Chapter 3 Block Ciphers and the Data Encryption Standard Last Chapter have considered: terminology classical cipher techniques substitution ciphers cryptanalysis using letter frequencies transposition
Computer and Data Security. Lecture 3 Block cipher and DES
Computer and Data Security Lecture 3 Block cipher and DES Stream Ciphers l Encrypts a digital data stream one bit or one byte at a time l One time pad is example; but practical limitations l Typical approach
Cryptography and Network Security Block Ciphers + DES. Lectured by Nguyễn Đức Thái
Cryptography and Network Security Block Ciphers + DES Lectured by Nguyễn Đức Thái Outline Block Cipher Principles Feistel Ciphers The Data Encryption Standard (DES) (Contents can be found in Chapter 3,
Symmetric Cryptography. Chapter 6
Symmetric Cryptography Chapter 6 Block vs Stream Ciphers Block ciphers process messages into blocks, each of which is then en/decrypted Like a substitution on very big characters 64-bits or more Stream
Network Security Essentials Chapter 2
Network Security Essentials Chapter 2 Fourth Edition by William Stallings Lecture slides by Lawrie Brown Encryption What is encryption? Why do we need it? No, seriously, let's discuss this. Why do we need
ICT 6541 Applied Cryptography. Hossen Asiful Mustafa
ICT 6541 Applied Cryptography Hossen Asiful Mustafa Encryption & Decryption Key (K) Plaintext (P) Encrypt (E) Ciphertext (C) C = E K (P) Same Key (K) Ciphertext (C) Decrypt (D) Plaintext (P) P = D K (C)
Data Encryption Standard
ECE 646 Lecture 7 Data Encryption Standard Required Reading W. Stallings, "Cryptography and Network-Security," 5th Edition, Chapter 3: Block Ciphers and the Data Encryption Standard Chapter 6.1: Multiple
Symmetric Encryption Algorithms
Symmetric Encryption Algorithms CS-480b Dick Steflik Text Network Security Essentials Wm. Stallings Lecture slides by Lawrie Brown Edited by Dick Steflik Symmetric Cipher Model Plaintext Encryption Algorithm
Dr. Jinyuan (Stella) Sun Dept. of Electrical Engineering and Computer Science University of Tennessee Fall 2010
CS 494/594 Computer and Network Security Dr. Jinyuan (Stella) Sun Dept. of Electrical Engineering and Computer Science University of Tennessee Fall 2010 1 Secret Key Cryptography Block cipher DES 3DES
Data Encryption Standard
ECE 646 Lecture 6 Data Encryption Standard Required Reading: I. W. Stallings, "Cryptography and Network-Security," 5th Edition, Chapter 3: Block Ciphers and the Data Encryption Standard Chapter 6.1: Multiple
Introduction to Modern Symmetric-Key Ciphers
Introduction to Modern Symmetric-Key Ciphers 1 Objectives Review a short history of DES. Define the basic structure of DES. List DES alternatives. Introduce the basic structure of AES. 2 Data Encryption
New Kid on the Block Practical Construction of Block Ciphers. Table of contents
New Kid on the Block Practical Construction of Block Ciphers Foundations of Cryptography Computer Science Department Wellesley College Fall 2016 Table of contents Introduction Substitution-permutation
Lecture 4: Symmetric Key Encryption
Lecture 4: Symmetric ey Encryption CS6903: Modern Cryptography Spring 2009 Nitesh Saxena Let s use the board, please take notes 2/20/2009 Lecture 1 - Introduction 2 Data Encryption Standard Encrypts by
Symmetric Key Algorithms. Definition. A symmetric key algorithm is an encryption algorithm where the same key is used for encrypting and decrypting.
Symmetric Key Algorithms Definition A symmetric key algorithm is an encryption algorithm where the same key is used for encrypting and decrypting. 1 Block cipher and stream cipher There are two main families
Cryptography and Network Security Chapter 3. Modern Block Ciphers. Block vs Stream Ciphers. Block Cipher Principles
Cryptography and Network Security Chapter 3 Fifth Edition by William Stallings Lecture slides by Lawrie Brown Chapter 3 Block Ciphers and the Data Encryption Standard All the afternoon Mungo had been working
CSCI 454/554 Computer and Network Security. Topic 3.1 Secret Key Cryptography Algorithms
CSCI 454/554 Computer and Network Security Topic 3.1 Secret Key Cryptography Algorithms Outline Introductory Remarks Feistel Cipher DES AES 2 Introduction Secret Keys or Secret Algorithms? Security by
Lecture 1 Applied Cryptography (Part 1)
Lecture 1 Applied Cryptography (Part 1) Patrick P. C. Lee Tsinghua Summer Course 2010 1-1 Roadmap Introduction to Security Introduction to Cryptography Symmetric key cryptography Hash and message authentication
Secret Key Algorithms (DES)
Secret Key Algorithms (DES) G. Bertoni L. Breveglieri Foundations of Cryptography - Secret Key pp. 1 / 34 Definition a symmetric key cryptographic algorithm is characterized by having the same key used
CENG 520 Lecture Note III
CENG 520 Lecture Note III Symmetric Ciphers block ciphers process messages in blocks, each of which is then en/decrypted like a substitution on very big characters 64-bits or more stream ciphers process
Network Security Essentials
Network Security Essentials Applications and Standards Third Edition William Stallings Chapter 2 Symmetric Encryption and Message Confidentiality Dr. BHARGAVI H. GOSWAMI Department of Computer Science
On the Design of Secure Block Ciphers
On the Design of Secure Block Ciphers Howard M. Heys and Stafford E. Tavares Department of Electrical and Computer Engineering Queen s University Kingston, Ontario K7L 3N6 email: tavares@ee.queensu.ca
Week 4. : Block Ciphers and DES
Week 4. : Block Ciphers and DES Model of Symmetric Cryptosystem Cryptanalyst Adversary M K E Insecure Channel D Plaintext M Ciphertext C Secure Channel Plaintext M Key K Shared Secret Key C = E K (M) D
CSC 474/574 Information Systems Security
CSC 474/574 Information Systems Security Topic 2.2 Secret Key Cryptography CSC 474/574 Dr. Peng Ning 1 Agenda Generic block cipher Feistel cipher DES Modes of block ciphers Multiple encryptions Message
Secret Key Algorithms (DES) Foundations of Cryptography - Secret Key pp. 1 / 34
Secret Key Algorithms (DES) Foundations of Cryptography - Secret Key pp. 1 / 34 Definition a symmetric key cryptographic algorithm is characterized by having the same key used for both encryption and decryption.
Block Encryption and DES
Block Encryption and DES Plain Text Block 1 Block 2 Block 3 Overview Raj Jain Washington University in Saint Louis Saint Louis, MO 63130 Jain@cse.wustl.edu Audio/Video recordings of this lecture are available
AIT 682: Network and Systems Security
AIT 682: Network and Systems Security Topic 3.1 Secret Key Cryptography Algorithms Instructor: Dr. Kun Sun Outline Introductory Remarks Feistel Cipher DES AES 2 Introduction Secret Keys or Secret Algorithms?
Lecture 3: Symmetric Key Encryption
Lecture 3: Symmetric Key Encryption CS996: Modern Cryptography Spring 2007 Nitesh Saxena Outline Symmetric Key Encryption Continued Discussion of Potential Project Topics Project proposal due 02/22/07
CSc 466/566. Computer Security. 6 : Cryptography Symmetric Key
1/56 CSc 466/566 Computer Security 6 : Cryptography Symmetric Key Version: 2012/02/22 16:14:16 Department of Computer Science University of Arizona collberg@gmail.com Copyright c 2012 Christian Collberg
Network Security. Lecture# 6 Lecture Slides Prepared by: Syed Irfan Ullah N.W.F.P. Agricultural University Peshawar
Network Security Lecture# 6 Lecture Slides Prepared by: Syed Irfan Ullah N.W.F.P. Agricultural University Peshawar Modern Block Ciphers now look at modern block ciphers one of the most widely used types
Modern Block Ciphers
Modern Block Ciphers now look at modern block ciphers one of the most widely used types of cryptographic algorithms provide secrecy /authentication services focus on DES (Data Encryption Standard) to illustrate
Introduction to Cryptology. Lecture 17
Introduction to Cryptology Lecture 17 Announcements HW7 due Thursday 4/7 Looking ahead: Practical constructions of CRHF Start Number Theory background Agenda Last time SPN (6.2) This time Feistel Networks
Cryptographic Algorithms - AES
Areas for Discussion Cryptographic Algorithms - AES CNPA - Network Security Joseph Spring Department of Computer Science Advanced Encryption Standard 1 Motivation Contenders Finalists AES Design Feistel
CHAPTER 6. SYMMETRIC CIPHERS C = E(K2, E(K1, P))
CHAPTER 6. SYMMETRIC CIPHERS Multiple encryption is a technique in which an encryption algorithm is used multiple times. In the first instance, plaintext is converted to ciphertext using the encryption
UNIT - II Traditional Symmetric-Key Ciphers. Cryptography & Network Security - Behrouz A. Forouzan
UNIT - II Traditional Symmetric-Key Ciphers 1 Objectives To define the terms and the concepts of symmetric key ciphers To emphasize the two categories of traditional ciphers: substitution and transposition
Double-DES, Triple-DES & Modes of Operation
Double-DES, Triple-DES & Modes of Operation Prepared by: Dr. Mohamed Abd-Eldayem Ref.: Cryptography and Network Security by William Stallings & Lecture slides by Lawrie Brown Multiple Encryption & DES
A Methodology for Differential-Linear Cryptanalysis and Its Applications
A Methodology for Differential-Linear Cryptanalysis and Its Applications Jiqiang Lu Presenter: Jian Guo Institute for Infocomm Research, Agency for Science, Technology and Research, 1 Fusionopolis Way,
Jordan University of Science and Technology
Jordan University of Science and Technology Cryptography and Network Security - CPE 542 Homework #III Handed to: Dr. Lo'ai Tawalbeh By: Ahmed Saleh Shatnawi 20012171020 On: 8/11/2005 Review Questions RQ3.3
The Rectangle Attack
The Rectangle Attack and Other Techniques for Cryptanalysis of Block Ciphers Orr Dunkelman Computer Science Dept. Technion joint work with Eli Biham and Nathan Keller Topics Block Ciphers Cryptanalysis
Block Ciphers Introduction
Technicalities Block Models Block Ciphers Introduction Orr Dunkelman Computer Science Department University of Haifa, Israel March 10th, 2013 Orr Dunkelman Cryptanalysis of Block Ciphers Seminar Introduction
Darshan Institute of Engineering & Technology Page Information Security (IS) UNIT-2 Conventional Encryption Techniques
Q 1. Draw and explain Feistel s structure for encryption and decryption. The exact realization of Feistel network depends on the choice of which parameters? Feistel cipher is based on the idea that instead
page 1 Introduction to Cryptography Benny Pinkas Lecture 3 November 18, 2008 Introduction to Cryptography, Benny Pinkas
Introduction to Cryptography Lecture 3 Benny Pinkas page 1 1 Pseudo-random generator Pseudo-random generator seed output s G G(s) (random, s =n) Deterministic function of s, publicly known G(s) = 2n Distinguisher
Introduction to Cryptography. Lecture 2. Benny Pinkas. Perfect Cipher. Perfect Ciphers. Size of key space
Perfect Cipher Introduction to Cryptography Lecture 2 Benny Pinkas What type of security would we like to achieve? Given C, the adversary has no idea what M is Impossible since adversary might have a-priori
PRNGs & DES. Luke Anderson. 16 th March University Of Sydney.
PRNGs & DES Luke Anderson luke@lukeanderson.com.au 16 th March 2018 University Of Sydney Overview 1. Pseudo Random Number Generators 1.1 Sources of Entropy 1.2 Desirable PRNG Properties 1.3 Real PRNGs
CSCE 813 Internet Security Symmetric Cryptography
CSCE 813 Internet Security Symmetric Cryptography Professor Lisa Luo Fall 2017 Previous Class Essential Internet Security Requirements Confidentiality Integrity Authenticity Availability Accountability
Goals of Modern Cryptography
Goals of Modern Cryptography Providing information security: Data Privacy Data Integrity and Authenticity in various computational settings. Data Privacy M Alice Bob The goal is to ensure that the adversary
Stream Ciphers and Block Ciphers
Stream Ciphers and Block Ciphers 2MMC10 Cryptology Fall 2015 Ruben Niederhagen October 6th, 2015 Introduction 2/32 Recall: Public-key crypto: Pair of keys: public key for encryption, private key for decryption.
Conventional Encryption: Modern Technologies
Conventional Encryption: Modern Technologies We mentioned that the statistical weakness in substitution ciphers is that they don t change the frequency of alphabetic letters. For example, if a substitution
Secret Key Cryptography
Secret Key Cryptography 1 Block Cipher Scheme Encrypt Plaintext block of length N Decrypt Secret key Cipher block of length N 2 Generic Block Encryption Convert a plaintext block into an encrypted block:
Block Cipher Operation. CS 6313 Fall ASU
Chapter 7 Block Cipher Operation 1 Outline q Multiple Encryption and Triple DES q Electronic Codebook q Cipher Block Chaining Mode q Cipher Feedback Mode q Output Feedback Mode q Counter Mode q XTS-AES
3 Symmetric Cryptography
CA4005: CRYPTOGRAPHY AND SECURITY PROTOCOLS 1 3 Symmetric Cryptography Symmetric Cryptography Alice Bob m Enc c = e k (m) k c c Dec m = d k (c) Symmetric cryptography uses the same secret key k for encryption
Chapter 6 Contemporary Symmetric Ciphers
Chapter 6 Contemporary Symmetric Ciphers "I am fairly familiar with all the forms of secret writings, and am myself the author of a trifling monograph upon the subject, in which I analyze one hundred and
Chapter 6: Contemporary Symmetric Ciphers
CPE 542: CRYPTOGRAPHY & NETWORK SECURITY Chapter 6: Contemporary Symmetric Ciphers Dr. Lo ai Tawalbeh Computer Engineering Department Jordan University of Science and Technology Jordan Why Triple-DES?
Block Cipher Involving Key Based Random Interlacing and Key Based Random Decomposition
Journal of Computer Science 6 (2): 133-140, 2010 ISSN 1549-3636 2010 Science Publications Block Cipher Involving Key Based Random Interlacing and Key Based Random Decomposition K. Anup Kumar and V.U.K.
CPS2323. Block Ciphers: The Data Encryption Standard (DES)
Block Ciphers: The Data Encryption Standard (DES) Content Block Ciphers: Constructing Pseudo Random Permutations using confusion/diffusion A call for an industry standard... and the NSA Lucifer and Feistel
Symmetric Encryption. Thierry Sans
Symmetric Encryption Thierry Sans Design principles (reminder) 1. Kerkoff Principle The security of a cryptosystem must not rely on keeping the algorithm secret 2. Diffusion Mixing-up symbols 3. Confusion
COS433/Math 473: Cryptography. Mark Zhandry Princeton University Spring 2018
COS433/Math 473: Cryptography Mark Zhandry Princeton University Spring 2018 Previously on COS 433 Confusion/Diffusion Paradigm f 1 f 2 f 3 f 4 f 5 f 6 Round π 1 f 7 f 8 f 9 f 10 f 11 f 12 π 2 Substitution
Cryptography and Network Security
Cryptography and Network Security Spring 2012 http://users.abo.fi/ipetre/crypto/ Lecture 14: Folklore, Course summary, Exam requirements Ion Petre Department of IT, Åbo Akademi University 1 Folklore on
Computer Security. 08. Cryptography Part II. Paul Krzyzanowski. Rutgers University. Spring 2018
Computer Security 08. Cryptography Part II Paul Krzyzanowski Rutgers University Spring 2018 March 23, 2018 CS 419 2018 Paul Krzyzanowski 1 Block ciphers Block ciphers encrypt a block of plaintext at a
Computer Security 3/23/18
s s encrypt a block of plaintext at a time and produce ciphertext Computer Security 08. Cryptography Part II Paul Krzyzanowski DES & AES are two popular block ciphers DES: 64 bit blocks AES: 128 bit blocks
Homework 2. Out: 09/23/16 Due: 09/30/16 11:59pm UNIVERSITY OF MARYLAND DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING
UNIVERSITY OF MARYLAND DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING ENEE 457 Computer Systems Security Instructor: Charalampos Papamanthou Homework 2 Out: 09/23/16 Due: 09/30/16 11:59pm Instructions
CIS 6930/4930 Computer and Network Security. Topic 3.1 Secret Key Cryptography (Cont d)
CIS 6930/4930 Computer and Network Security Topic 3.1 Secret Key Cryptography (Cont d) 1 Principles for S-Box Design S-box is the only non-linear part of DES Each row in the S-Box table should be a permutation
Analysis of the Use of Whirlpool s S-box, S1 and S2 SEED s S- box in AES Algorithm with SAC Test Novita Angraini, Bety Hayat Susanti, Magfirawaty
Information Systems International Conference (ISICO), 2 4 December 2013 Analysis of the Use of Whirlpool s S-box, S1 and S2 SEED s S- box in AES Algorithm with SAC Test Novita Angraini, Bety Hayat Susanti,
6 Block Ciphers. 6.1 Block Ciphers CA642: CRYPTOGRAPHY AND NUMBER THEORY 1
CA642: CRYPTOGRAPHY AND NUMBER THEORY 1 6 Block Ciphers 6.1 Block Ciphers Block Ciphers Plaintext is divided into blocks of fixed length and every block is encrypted one at a time. A block cipher is a
Stream Ciphers and Block Ciphers
Stream Ciphers and Block Ciphers Ruben Niederhagen September 18th, 2013 Introduction 2/22 Recall from last lecture: Public-key crypto: Pair of keys: public key for encryption, private key for decryption.
7. Symmetric encryption. symmetric cryptography 1
CIS 5371 Cryptography 7. Symmetric encryption symmetric cryptography 1 Cryptographic systems Cryptosystem: t (MCKK GED) (M,C,K,K,G,E,D) M, plaintext message space C, ciphertext message space K, K, encryption
Cryptography and Network Security
Cryptography and Network Security Spring 2012 http://users.abo.fi/ipetre/crypto/ Lecture 6: Advanced Encryption Standard (AES) Ion Petre Department of IT, Åbo Akademi University 1 Origin of AES 1999: NIST
Cryptography III: Symmetric Ciphers
Cryptography III: Symmetric Ciphers Computer Security Lecture 12 David Aspinall School of Informatics University of Edinburgh 14th February 2008 Outline Stream ciphers Block ciphers DES and Rijndael Summary
Secret Key Cryptography (Spring 2004)
Secret Key Cryptography (Spring 2004) Instructor: Adi Shamir Teaching assistant: Eran Tromer 1 Background Lecture notes: DES Until early 1970 s: little cryptographic research in industry and academcy.
Cryptography MIS
Cryptography MIS-5903 http://community.mis.temple.edu/mis5903sec011s17/ Cryptography History Substitution Monoalphabetic Polyalphabetic (uses multiple alphabets) uses Vigenere Table Scytale cipher (message
Jaap van Ginkel Security of Systems and Networks
Jaap van Ginkel Security of Systems and Networks November 4, 2013 Part 4 Modern Crypto Block Ciphers (Iterated) Block Cipher Plaintext and ciphertext consist of fixed-sized blocks Ciphertext obtained from
A Block Cipher using Feistal s Approach Involving Permutation and Mixing of the Plaintext and the Additive Inverse of Key Matrix
Journal of omputer Science 4 (): 7-4, 8 ISSN 549-3636 8 Science Publications A Block ipher using Feistal s Approach Involving Permutation and Mixing of the Plaintext and the Additive Inverse of Key Matrix
International Journal for Research in Applied Science & Engineering Technology (IJRASET) Performance Comparison of Cryptanalysis Techniques over DES
Performance Comparison of Cryptanalysis Techniques over DES Anupam Kumar 1, Aman Kumar 2, Sahil Jain 3, P Kiranmai 4 1,2,3,4 Dept. of Computer Science, MAIT, GGSIP University, Delhi, INDIA Abstract--The
APNIC elearning: Cryptography Basics
APNIC elearning: Cryptography Basics 27 MAY 2015 03:00 PM AEST Brisbane (UTC+10) Issue Date: Revision: Introduction Presenter Sheryl Hermoso Training Officer sheryl@apnic.net Specialties: Network Security
Modern Symmetric Block cipher
Modern Symmetric Block cipher 81 Shannon's Guide to Good Ciphers Amount of secrecy should determine amount of labour appropriate for encryption and decryption The set of keys and enciphering algorithm
Sankalchand Patel College of Engineering, Visnagar Department of Computer Engineering & Information Technology. Question Bank
Sankalchand Patel College of Engineering, Visnagar Department of Computer Engineering & Information Technology Question Bank Subject: Information Security (160702) Class: BE Sem. VI (CE/IT) Unit-1: Conventional
CRYPTOLOGY KEY MANAGEMENT CRYPTOGRAPHY CRYPTANALYSIS. Cryptanalytic. Brute-Force. Ciphertext-only Known-plaintext Chosen-plaintext Chosen-ciphertext
CRYPTOLOGY CRYPTOGRAPHY KEY MANAGEMENT CRYPTANALYSIS Cryptanalytic Brute-Force Ciphertext-only Known-plaintext Chosen-plaintext Chosen-ciphertext 58 Types of Cryptographic Private key (Symmetric) Public
Technion - Computer Science Department - Technical Report CS
[13] National Bureau of Standards, DS Modes of Operation, U.S. Department of Commerce, FIPS pub. 81, December 1980. [14] Paul C. van Oorschot, Michael J. Wiener, A Known Plaintext Attack on Two-Key Triple
CPSC 467: Cryptography and Computer Security
CPSC 467: Cryptography and Computer Security Instructor: Michael Fischer Lecture by Ewa Syta Lecture 7 September 23, 2015 CPSC 467, Lecture 7 1/1 Advanced Encryption Standard AES Alternatives CPSC 467,
CIS 4360 Introduction to Computer Security Fall WITH ANSWERS in bold. First Midterm
CIS 4360 Introduction to Computer Security Fall 2010 WITH ANSWERS in bold Name:.................................... Number:............ First Midterm Instructions This is a closed-book examination. Maximum
Computational Security, Stream and Block Cipher Functions
Computational Security, Stream and Block Cipher Functions 18 March 2019 Lecture 3 Most Slides Credits: Steve Zdancewic (UPenn) 18 March 2019 SE 425: Communication and Information Security 1 Topics for
3 Symmetric Key Cryptography 3.1 Block Ciphers Symmetric key strength analysis Electronic Code Book Mode (ECB) Cipher Block Chaining Mode (CBC) Some
3 Symmetric Key Cryptography 3.1 Block Ciphers Symmetric key strength analysis Electronic Code Book Mode (ECB) Cipher Block Chaining Mode (CBC) Some popular block ciphers Triple DES Advanced Encryption
Block Ciphers. Lucifer, DES, RC5, AES. CS 470 Introduction to Applied Cryptography. Ali Aydın Selçuk. CS470, A.A.Selçuk Block Ciphers 1
Block Ciphers Lucifer, DES, RC5, AES CS 470 Introduction to Applied Cryptography Ali Aydın Selçuk CS470, A.A.Selçuk Block Ciphers 1 ... Block Ciphers & S-P Networks Block Ciphers: Substitution ciphers
Information Security and Cryptography 資訊安全與密碼學. Lecture 6 April 8, 2015 洪國寶
Information Security and Cryptography 資訊安全與密碼學 Lecture 6 April 8, 2015 洪國寶 1 Outline Review Cryptology Introduction and terminologies Definition of cryptosystem and cryptanalysis Types of encryption Symmetric
CS6701- CRYPTOGRAPHY AND NETWORK SECURITY UNIT 2 NOTES
CS6701- CRYPTOGRAPHY AND NETWORK SECURITY UNIT 2 NOTES PREPARED BY R.CYNTHIA PRIYADHARSHINI AP/IT/SREC Block Ciphers A block cipher is an encryption/decryption scheme in which a block of plaintext is treated
U-II BLOCK CIPHER ALGORITHMS
U-II BLOCK CIPHER ALGORITHMS IDEA: Idea is block cipher similar to DES Works on 64 bit plaintext block Key is longer and consist of 128 bits Idea is reversible like DES i.e. same algorithm can be used
Introduction. Secret Key Cryptography. Outline. Secrets? (Cont d) Secret Keys or Secret Algorithms? Introductory Remarks Feistel Cipher DES AES
Outline CSCI 454/554 Computer and Network Security Introductory Remarks Feistel Cipher DES AES Topic 3.1 Secret Key Cryptography Algorithms 2 Secret Keys or Secret Algorithms? Introduction Security by
Syrvey on block ciphers
Syrvey on block ciphers Anna Rimoldi Department of Mathematics - University of Trento BunnyTn 2012 A. Rimoldi (Univ. Trento) Survey on block ciphers 12 March 2012 1 / 21 Symmetric Key Cryptosystem M-Source
Sirindhorn International Institute of Technology Thammasat University
1 Name...ID....Section. Seat No.. Sirindhorn International Institute of Technology Thammasat University Midterm Examination: Semester 2/2007 Course Title : CSS 322 Security and Cryptography Instructor
Conventional Encryption Principles Conventional Encryption Algorithms Cipher Block Modes of Operation Location of Encryption Devices Key Distribution
Ola Flygt Växjö University, Sweden http://w3.msi.vxu.se/users/ofl/ Ola.Flygt@vxu.se +46 470 70 86 49 1 Conventional Encryption Principles Conventional Encryption Algorithms Cipher Block Modes of Operation
The FastDES: A New Look of Data Encryption Standard
The FastDES: A New Look of Data Encryption Standard Muhammad Nawaz Khan School of Electrical Engineering & Computer Science (SEECS), National University of Science & Technology (NUST), Islamabad, Pakistan.
Network Security 網路安全. Lecture 3 March 16, 2015 洪國寶
Network Security 網路安全 Lecture 3 March 16, 2015 洪國寶 1 Outline Review: Symmetric encryption -- Classical techniques (Cont.) Symmetric encryption -- Modern techniques secure encryption schemes modern symmetric
Symmetric Key Encryption. Symmetric Key Encryption. Advanced Encryption Standard ( AES ) DES DES DES 08/01/2015. DES and 3-DES.
Symmetric Key Encryption Symmetric Key Encryption and 3- Tom Chothia Computer Security: Lecture 2 Padding Block cipher modes Advanced Encryption Standard ( AES ) AES is a state-of-the-art block cipher.
Cryptography and Network Security. Sixth Edition by William Stallings
Cryptography and Network Security Sixth Edition by William Stallings Chapter 5 Advanced Encryption Standard Advance Encryption Standard Topics Origin of AES Basic AES Inside Algorithm Final Notes Origins
P2_L6 Symmetric Encryption Page 1
P2_L6 Symmetric Encryption Page 1 Reference: Computer Security by Stallings and Brown, Chapter 20 Symmetric encryption algorithms are typically block ciphers that take thick size input. In this lesson,
Implementation and Performance analysis of Skipjack & Rijndael Algorithms. by Viswnadham Sanku ECE646 Project Fall-2001
Implementation and Performance analysis of Skipjack & Rijndael Algorithms by Viswnadham Sanku ECE646 Project Fall-2001 TABLE OF CONTENTS TABLE OF CONTENTS 2 1. OBJECTIVE 3 2. SKIPJACK CIPHER 3 2.1 CIPHER
Fundamentals of Cryptography
Fundamentals of Cryptography Topics in Quantum-Safe Cryptography June 23, 2016 Part III Data Encryption Standard The Feistel network design m m 0 m 1 f k 1 1 m m 1 2 f k 2 2 DES uses a Feistel network
Lecturers: Mark D. Ryan and David Galindo. Cryptography Slide: 24
Assume encryption and decryption use the same key. Will discuss how to distribute key to all parties later Symmetric ciphers unusable for authentication of sender Lecturers: Mark D. Ryan and David Galindo.