Simplified Idea Algorithm
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Grade 6 Reading Student At–Home Activity Packet
Printer Warning: This packet is lengthy. Determine whether you want to print both sections, or only print Section 1 or 2. Grade 6 Reading Student At–Home Activity Packet This At–Home Activity packet includes two parts, Section 1 and Section 2, each with approximately 10 lessons in it. We recommend that your student complete one lesson each day. Most lessons can be completed independently. However, there are some lessons that would benefit from the support of an adult. If there is not an adult available to help, don’t worry! Just skip those lessons. Encourage your student to just do the best they can with this content—the most important thing is that they continue to work on their reading! Flip to see the Grade 6 Reading activities included in this packet! © 2020 Curriculum Associates, LLC. All rights reserved. Section 1 Table of Contents Grade 6 Reading Activities in Section 1 Lesson Resource Instructions Answer Key Page 1 Grade 6 Ready • Read the Guided Practice: Answers will vary. 10–11 Language Handbook, Introduction. Sample answers: Lesson 9 • Complete the 1. Wouldn’t it be fun to learn about Varying Sentence Guided Practice. insect colonies? Patterns • Complete the 2. When I looked at the museum map, Independent I noticed a new insect exhibit. Lesson 9 Varying Sentence Patterns Introduction Good writers use a variety of sentence types. They mix short and long sentences, and they find different ways to start sentences. Here are ways to improve your writing: Practice. Use different sentence types: statements, questions, imperatives, and exclamations. Use different sentence structures: simple, compound, complex, and compound-complex. -
Vector Boolean Functions: Applications in Symmetric Cryptography
Vector Boolean Functions: Applications in Symmetric Cryptography José Antonio Álvarez Cubero Departamento de Matemática Aplicada a las Tecnologías de la Información y las Comunicaciones Universidad Politécnica de Madrid This dissertation is submitted for the degree of Doctor Ingeniero de Telecomunicación Escuela Técnica Superior de Ingenieros de Telecomunicación November 2015 I would like to thank my wife, Isabel, for her love, kindness and support she has shown during the past years it has taken me to finalize this thesis. Furthermore I would also liketo thank my parents for their endless love and support. Last but not least, I would like to thank my loved ones such as my daughter and sisters who have supported me throughout entire process, both by keeping me harmonious and helping me putting pieces together. I will be grateful forever for your love. Declaration The following papers have been published or accepted for publication, and contain material based on the content of this thesis. 1. [7] Álvarez-Cubero, J. A. and Zufiria, P. J. (expected 2016). Algorithm xxx: VBF: A library of C++ classes for vector Boolean functions in cryptography. ACM Transactions on Mathematical Software. (In Press: http://toms.acm.org/Upcoming.html) 2. [6] Álvarez-Cubero, J. A. and Zufiria, P. J. (2012). Cryptographic Criteria on Vector Boolean Functions, chapter 3, pages 51–70. Cryptography and Security in Computing, Jaydip Sen (Ed.), http://www.intechopen.com/books/cryptography-and-security-in-computing/ cryptographic-criteria-on-vector-boolean-functions. (Published) 3. [5] Álvarez-Cubero, J. A. and Zufiria, P. J. (2010). A C++ class for analysing vector Boolean functions from a cryptographic perspective. -
The Data Encryption Standard (DES) – History
Chair for Network Architectures and Services Department of Informatics TU München – Prof. Carle Network Security Chapter 2 Basics 2.1 Symmetric Cryptography • Overview of Cryptographic Algorithms • Attacking Cryptographic Algorithms • Historical Approaches • Foundations of Modern Cryptography • Modes of Encryption • Data Encryption Standard (DES) • Advanced Encryption Standard (AES) Cryptographic algorithms: outline Cryptographic Algorithms Symmetric Asymmetric Cryptographic Overview En- / Decryption En- / Decryption Hash Functions Modes of Cryptanalysis Background MDC’s / MACs Operation Properties DES RSA MD-5 AES Diffie-Hellman SHA-1 RC4 ElGamal CBC-MAC Network Security, WS 2010/11, Chapter 2.1 2 Basic Terms: Plaintext and Ciphertext Plaintext P The original readable content of a message (or data). P_netsec = „This is network security“ Ciphertext C The encrypted version of the plaintext. C_netsec = „Ff iThtIiDjlyHLPRFxvowf“ encrypt key k1 C P key k2 decrypt In case of symmetric cryptography, k1 = k2. Network Security, WS 2010/11, Chapter 2.1 3 Basic Terms: Block cipher and Stream cipher Block cipher A cipher that encrypts / decrypts inputs of length n to outputs of length n given the corresponding key k. • n is block length Most modern symmetric ciphers are block ciphers, e.g. AES, DES, Twofish, … Stream cipher A symmetric cipher that generats a random bitstream, called key stream, from the symmetric key k. Ciphertext = key stream XOR plaintext Network Security, WS 2010/11, Chapter 2.1 4 Cryptographic algorithms: overview -
Investigating Profiled Side-Channel Attacks Against the DES Key
IACR Transactions on Cryptographic Hardware and Embedded Systems ISSN 2569-2925, Vol. 2020, No. 3, pp. 22–72. DOI:10.13154/tches.v2020.i3.22-72 Investigating Profiled Side-Channel Attacks Against the DES Key Schedule Johann Heyszl1[0000−0002−8425−3114], Katja Miller1, Florian Unterstein1[0000−0002−8384−2021], Marc Schink1, Alexander Wagner1, Horst Gieser2, Sven Freud3, Tobias Damm3[0000−0003−3221−7207], Dominik Klein3[0000−0001−8174−7445] and Dennis Kügler3 1 Fraunhofer Institute for Applied and Integrated Security (AISEC), Germany, [email protected] 2 Fraunhofer Research Institution for Microsystems and Solid State Technologies (EMFT), Germany, [email protected] 3 Bundesamt für Sicherheit in der Informationstechnik (BSI), Germany, [email protected] Abstract. Recent publications describe profiled single trace side-channel attacks (SCAs) against the DES key-schedule of a “commercially available security controller”. They report a significant reduction of the average remaining entropy of cryptographic keys after the attack, with surprisingly large, key-dependent variations of attack results, and individual cases with remaining key entropies as low as a few bits. Unfortunately, they leave important questions unanswered: Are the reported wide distributions of results plausible - can this be explained? Are the results device- specific or more generally applicable to other devices? What is the actual impact on the security of 3-key triple DES? We systematically answer those and several other questions by analyzing two commercial security controllers and a general purpose microcontroller. We observe a significant overall reduction and, importantly, also observe a large key-dependent variation in single DES key security levels, i.e. -
Block Ciphers and the Data Encryption Standard
Lecture 3: Block Ciphers and the Data Encryption Standard Lecture Notes on “Computer and Network Security” by Avi Kak ([email protected]) January 26, 2021 3:43pm ©2021 Avinash Kak, Purdue University Goals: To introduce the notion of a block cipher in the modern context. To talk about the infeasibility of ideal block ciphers To introduce the notion of the Feistel Cipher Structure To go over DES, the Data Encryption Standard To illustrate important DES steps with Python and Perl code CONTENTS Section Title Page 3.1 Ideal Block Cipher 3 3.1.1 Size of the Encryption Key for the Ideal Block Cipher 6 3.2 The Feistel Structure for Block Ciphers 7 3.2.1 Mathematical Description of Each Round in the 10 Feistel Structure 3.2.2 Decryption in Ciphers Based on the Feistel Structure 12 3.3 DES: The Data Encryption Standard 16 3.3.1 One Round of Processing in DES 18 3.3.2 The S-Box for the Substitution Step in Each Round 22 3.3.3 The Substitution Tables 26 3.3.4 The P-Box Permutation in the Feistel Function 33 3.3.5 The DES Key Schedule: Generating the Round Keys 35 3.3.6 Initial Permutation of the Encryption Key 38 3.3.7 Contraction-Permutation that Generates the 48-Bit 42 Round Key from the 56-Bit Key 3.4 What Makes DES a Strong Cipher (to the 46 Extent It is a Strong Cipher) 3.5 Homework Problems 48 2 Computer and Network Security by Avi Kak Lecture 3 Back to TOC 3.1 IDEAL BLOCK CIPHER In a modern block cipher (but still using a classical encryption method), we replace a block of N bits from the plaintext with a block of N bits from the ciphertext. -
Analysis of FOX Summary
12/09/2008 Analysis of FOX Jorge Nakahara Jr [email protected] Presented by: Mads Rasmussen [email protected] SBSeg 2008, Gramado, RS, Brazil Summary • The FOX block cippyher family • Information leakage in FOX • Impossible-Differential Analysis • Conclusions SBSeg 2008, Gramado, RS, Brazil 1 12/09/2008 The FOX Cipher Family • Designers: P. Junod and S. Vaudenay (2004) • New name: IDEA-NXT • Owned by Mediacrypt A.G. • Lai-Massey structure, like IDEA cipher • Two main ciphers: FOX64 and FOX128 • Byte-oriented design: byte are elements of GF(2 8) = GF(2)[x]/(x8+x7+x6+x5+x4 +x3+1) SBSeg 2008, Gramado, RS, Brazil The FOX Cipher Family • Each round of FOX64 uses a bijective mapping called f32 consisting of an MDS matrix, xor with two round subkeys, and an 8x8-bit S-box • Each round of FOX128 uses a bijective mapping called f64, consisting of an MDS matrix, xor with two round subkeys and an 8x8-bit S-box • To break the round symmetry, there is a linear transformation called orthomorphism (or) at the end of each round. SBSeg 2008, Gramado, RS, Brazil 2 12/09/2008 The FOX Cipher Family Cipher Block Size Key Size #rounds (bits) (bits) FOX64 64 128 16 FOX128 128 256 16 FOX64/k/r 64 k r (0 ≤ k ≤ 256) (12 ≤ r ≤ 255) FOX128/k/r 128 k r (0 ≤ k ≤ 256) (12 ≤ r ≤ 255) SBSeg 2008, Gramado, RS, Brazil FOX64 SBSeg 2008, Gramado, RS, Brazil 3 12/09/2008 Information Leakage • Information leakage: discover (non-trivial) internal cipher data using only (known) plaintext-ciphertext pairs. -
KLEIN: a New Family of Lightweight Block Ciphers
KLEIN: A New Family of Lightweight Block Ciphers Zheng Gong1, Svetla Nikova1;2 and Yee Wei Law3 1Faculty of EWI, University of Twente, The Netherlands fz.gong, [email protected] 2 Dept. ESAT/SCD-COSIC, Katholieke Universiteit Leuven, Belgium 3 Department of EEE, The University of Melbourne, Australia [email protected] Abstract Resource-efficient cryptographic primitives become fundamental for realizing both security and efficiency in embedded systems like RFID tags and sensor nodes. Among those primitives, lightweight block cipher plays a major role as a building block for security protocols. In this paper, we describe a new family of lightweight block ciphers named KLEIN, which is designed for resource-constrained devices such as wireless sensors and RFID tags. Compared to the related proposals, KLEIN has ad- vantage in the software performance on legacy sensor platforms, while its hardware implementation can be compact as well. Key words. Block cipher, Wireless sensor network, Low-resource implementation. 1 Introduction With the development of wireless communication and embedded systems, we become increasingly de- pendent on the so called pervasive computing; examples are smart cards, RFID tags, and sensor nodes that are used for public transport, pay TV systems, smart electricity meters, anti-counterfeiting, etc. Among those applications, wireless sensor networks (WSNs) have attracted more and more attention since their promising applications, such as environment monitoring, military scouting and healthcare. On resource-limited devices the choice of security algorithms should be very careful by consideration of the implementation costs. Symmetric-key algorithms, especially block ciphers, still play an important role for the security of the embedded systems. -
Known and Chosen Key Differential Distinguishers for Block Ciphers
Known and Chosen Key Differential Distinguishers for Block Ciphers Ivica Nikoli´c1?, Josef Pieprzyk2, Przemys law Soko lowski2;3, Ron Steinfeld2 1 University of Luxembourg, Luxembourg 2 Macquarie University, Australia 3 Adam Mickiewicz University, Poland [email protected], [email protected], [email protected], [email protected] Abstract. In this paper we investigate the differential properties of block ciphers in hash function modes of operation. First we show the impact of differential trails for block ciphers on collision attacks for various hash function constructions based on block ciphers. Further, we prove the lower bound for finding a pair that follows some truncated differential in case of a random permutation. Then we present open-key differential distinguishers for some well known round-reduced block ciphers. Keywords: Block cipher, differential attack, open-key distinguisher, Crypton, Hierocrypt, SAFER++, Square. 1 Introduction Block ciphers play an important role in symmetric cryptography providing the basic tool for encryp- tion. They are the oldest and most scrutinized cryptographic tool. Consequently, they are the most trusted cryptographic algorithms that are often used as the underlying tool to construct other cryp- tographic algorithms. One such application of block ciphers is for building compression functions for the hash functions. There are many constructions (also called hash function modes) for turning a block cipher into a compression function. Probably the most popular is the well-known Davies-Meyer mode. Preneel et al. in [27] have considered all possible modes that can be defined for a single application of n-bit block cipher in order to produce an n-bit compression function. -
Internet Engineering Task Force (IETF) S. Kanno Request for Comments: 6367 NTT Software Corporation Category: Informational M
Internet Engineering Task Force (IETF) S. Kanno Request for Comments: 6367 NTT Software Corporation Category: Informational M. Kanda ISSN: 2070-1721 NTT September 2011 Addition of the Camellia Cipher Suites to Transport Layer Security (TLS) Abstract This document specifies forty-two cipher suites for the Transport Security Layer (TLS) protocol to support the Camellia encryption algorithm as a block cipher. Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6367. Copyright Notice Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. -
Development of the Advanced Encryption Standard
Volume 126, Article No. 126024 (2021) https://doi.org/10.6028/jres.126.024 Journal of Research of the National Institute of Standards and Technology Development of the Advanced Encryption Standard Miles E. Smid Formerly: Computer Security Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA [email protected] Strong cryptographic algorithms are essential for the protection of stored and transmitted data throughout the world. This publication discusses the development of Federal Information Processing Standards Publication (FIPS) 197, which specifies a cryptographic algorithm known as the Advanced Encryption Standard (AES). The AES was the result of a cooperative multiyear effort involving the U.S. government, industry, and the academic community. Several difficult problems that had to be resolved during the standard’s development are discussed, and the eventual solutions are presented. The author writes from his viewpoint as former leader of the Security Technology Group and later as acting director of the Computer Security Division at the National Institute of Standards and Technology, where he was responsible for the AES development. Key words: Advanced Encryption Standard (AES); consensus process; cryptography; Data Encryption Standard (DES); security requirements, SKIPJACK. Accepted: June 18, 2021 Published: August 16, 2021; Current Version: August 23, 2021 This article was sponsored by James Foti, Computer Security Division, Information Technology Laboratory, National Institute of Standards and Technology (NIST). The views expressed represent those of the author and not necessarily those of NIST. https://doi.org/10.6028/jres.126.024 1. Introduction In the late 1990s, the National Institute of Standards and Technology (NIST) was about to decide if it was going to specify a new cryptographic algorithm standard for the protection of U.S. -
Chapter 3 – Block Ciphers and the Data Encryption Standard
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 ciphers process messages a bit or byte at a time when en/decrypting – Many current ciphers are block ciphers • Better analyzed. • Broader range of applications. Block vs Stream Ciphers Block Cipher Principles • Block ciphers look like an extremely large substitution • Would need table of 264 entries for a 64-bit block • Arbitrary reversible substitution cipher for a large block size is not practical – 64-bit general substitution block cipher, key size 264! • Most symmetric block ciphers are based on a Feistel Cipher Structure • Needed since must be able to decrypt ciphertext to recover messages efficiently Ideal Block Cipher Substitution-Permutation Ciphers • in 1949 Shannon introduced idea of substitution- permutation (S-P) networks – modern substitution-transposition product cipher • These form the basis of modern block ciphers • S-P networks are based on the two primitive cryptographic operations we have seen before: – substitution (S-box) – permutation (P-box) (transposition) • Provide confusion and diffusion of message Diffusion and Confusion • Introduced by Claude Shannon to thwart cryptanalysis based on statistical analysis – Assume the attacker has some knowledge of the statistical characteristics of the plaintext • Cipher needs to completely obscure statistical properties of original message • A one-time pad does this Diffusion -
A Block Cipher Algorithm to Enhance the Avalanche Effect Using Dynamic Key- Dependent S-Box and Genetic Operations 1Balajee Maram and 2J.M
International Journal of Pure and Applied Mathematics Volume 119 No. 10 2018, 399-418 ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu Special Issue ijpam.eu A Block Cipher Algorithm to Enhance the Avalanche Effect Using Dynamic Key- Dependent S-Box and Genetic Operations 1Balajee Maram and 2J.M. Gnanasekar 1Department of CSE, GMRIT, Rajam, India. Research and Development Centre, Bharathiar University, Coimbatore. [email protected] 2Department of Computer Science & Engineering, Sri Venkateswara College of Engineering, Sriperumbudur Tamil Nadu. [email protected] Abstract In digital data security, an encryption technique plays a vital role to convert digital data into intelligible form. In this paper, a light-weight S- box is generated that depends on Pseudo-Random-Number-Generators. According to shared-secret-key, all the Pseudo-Random-Numbers are scrambled and input to the S-box. The complexity of S-box generation is very simple. Here the plain-text is encrypted using Genetic Operations and S-box which is generated based on shared-secret-key. The proposed algorithm is experimentally investigates the complexity, quality and performance using the S-box parameters which includes Hamming Distance, Balanced Output and the characteristic of cryptography is Avalanche Effect. Finally the comparison results motivates that the dynamic key-dependent S-box has good quality and performance than existing algorithms. 399 International Journal of Pure and Applied Mathematics Special Issue Index Terms:S-BOX, data security, random number, cryptography, genetic operations. 400 International Journal of Pure and Applied Mathematics Special Issue 1. Introduction In public network, several types of attacks1 can be avoided by applying Data Encryption/Decryption2.