Optimizing the Confidentiality of Lecturer Database Using Elgamal Algorithm
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Models and Algorithms for Physical Cryptanalysis
MODELS AND ALGORITHMS FOR PHYSICAL CRYPTANALYSIS Dissertation zur Erlangung des Grades eines Doktor-Ingenieurs der Fakult¨at fur¨ Elektrotechnik und Informationstechnik an der Ruhr-Universit¨at Bochum von Kerstin Lemke-Rust Bochum, Januar 2007 ii Thesis Advisor: Prof. Dr.-Ing. Christof Paar, Ruhr University Bochum, Germany External Referee: Prof. Dr. David Naccache, Ecole´ Normale Sup´erieure, Paris, France Author contact information: [email protected] iii Abstract This thesis is dedicated to models and algorithms for the use in physical cryptanalysis which is a new evolving discipline in implementation se- curity of information systems. It is based on physically observable and manipulable properties of a cryptographic implementation. Physical observables, such as the power consumption or electromag- netic emanation of a cryptographic device are so-called `side channels'. They contain exploitable information about internal states of an imple- mentation at runtime. Physical effects can also be used for the injec- tion of faults. Fault injection is successful if it recovers internal states by examining the effects of an erroneous state propagating through the computation. This thesis provides a unified framework for side channel and fault cryptanalysis. Its objective is to improve the understanding of physi- cally enabled cryptanalysis and to provide new models and algorithms. A major motivation for this work is that methodical improvements for physical cryptanalysis can also help in developing efficient countermea- sures for securing cryptographic implementations. This work examines differential side channel analysis of boolean and arithmetic operations which are typical primitives in cryptographic algo- rithms. Different characteristics of these operations can support a side channel analysis, even of unknown ciphers. -
Effects of Architecture on Information Leakage of a Hardware Advanced Encryption Standard Implementation Eric A
Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 9-13-2012 Effects of Architecture on Information Leakage of a Hardware Advanced Encryption Standard Implementation Eric A. Koziel Follow this and additional works at: https://scholar.afit.edu/etd Part of the Computer and Systems Architecture Commons, and the Information Security Commons Recommended Citation Koziel, Eric A., "Effects of Architecture on Information Leakage of a Hardware Advanced Encryption Standard Implementation" (2012). Theses and Dissertations. 1127. https://scholar.afit.edu/etd/1127 This Thesis is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. EFFECTS OF ARCHITECTURE ON INFORMATION LEAKAGE OF A HARDWARE ADVANCED ENCRYPTION STANDARD IMPLEMENTATION THESIS Eric A. Koziel AFIT/GCO/ENG/12-25 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED The views expressed in this thesis are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT/GCO/ENG/12-25 EFFECTS OF ARCHITECTURE ON INFORMATION LEAKAGE OF A HARDWARE ADVANCED ENCRYPTION STANDARD IMPLEMENTATION THESIS Presented to the Faculty Department of Electrical & Computer Engineering Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Master of Science in Cyber Operations Eric A. -
Some Words on Cryptanalysis of Stream Ciphers Maximov, Alexander
Some Words on Cryptanalysis of Stream Ciphers Maximov, Alexander 2006 Link to publication Citation for published version (APA): Maximov, A. (2006). Some Words on Cryptanalysis of Stream Ciphers. Department of Information Technology, Lund Univeristy. Total number of authors: 1 General rights Unless other specific re-use rights are stated the following general rights apply: Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Read more about Creative commons licenses: https://creativecommons.org/licenses/ Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. LUND UNIVERSITY PO Box 117 221 00 Lund +46 46-222 00 00 Some Words on Cryptanalysis of Stream Ciphers Alexander Maximov Ph.D. Thesis, June 16, 2006 Alexander Maximov Department of Information Technology Lund University Box 118 S-221 00 Lund, Sweden e-mail: [email protected] http://www.it.lth.se/ ISBN: 91-7167-039-4 ISRN: LUTEDX/TEIT-06/1035-SE c Alexander Maximov, 2006 Abstract n the world of cryptography, stream ciphers are known as primitives used Ito ensure privacy over a communication channel. -
Cryptography Weekly Independent Teaching Activities Teaching Credits Hours 4 6
COURSE OUTLINE (1) GENERAL SCHOOL SCHOOL OF SCIENCES ACADEMIC UNIT DEPARTMENT OF MATHEMATICS LEVEL OF STUDIES UNDERGRADUATE PROGRAM COURSE CODE 311-2003 SEMESTER F COURSE TITLE CRYPTOGRAPHY WEEKLY INDEPENDENT TEACHING ACTIVITIES TEACHING CREDITS HOURS 4 6 COURSE TYPE Special background PREREQUISITE COURSES: NO LANGUAGE OF INSTRUCTION and GREEK EXAMINATIONS: IS THE COURSE OFFERED TO YES ERASMUS STUDENTS COURSE WEBSITE (URL) http://www.math.aegean.gr/index.php/en/academics/undergraduate- programs (2) LEARNING OUTCOMES Learning outcomes In this course the students are introduced to the basic complexity theory and how computational difficulty in solving problems can be exploited to build secure cryptographic protocols. The lectures are, then, focused on some elementary cryptographic schemes like Caesar’s cipher, general substitution ciphers, polyalphabetic ciphers and how they can be broken efficiently. Then the students are introduced to Shannon’s cryptographic principles of confusion and diffusion and how they lead to the Feistel-based block ciphers. Then, as case studies, the block ciphers DES, CAST-128 and AES are presented along with analysis of their security properties. In the middle of the course, the students are introduced to public key cryptography and the RSA, ElGamal scheme and the foundations of Elliptic Curve Cryptography as well as the state of the art in the cryptanalysis of RSA and ECC. The aim of this course is mainly to introduce the students into the basic concepts of cryptography and cryptanalysis. At the end of the course, they could develop and analyse certain cryptographic systems and they could be ready to use and modify certain cryptanalysis techniques. -
Public Key Cryptography and RSA Cryptosystem
EE 418 Network Security and Cryptography Lecture #10 November 1, 2016 RSA and ElGamal Public Key Cryptosystems. Introduction to Key Distribution. Diffie-Hellman Key Distribution. Lecture notes prepared by Professor Radha Poovendran. Tamara Bonaci Department of Electrical Engineering University of Washington, Seattle Outline: 1. Review: Public Key Cryptography { The Discrete logarithm problem { ElGamal cryptosystem 2. Introduction to Key Distribution Problem 3. Diffie-Hellman Key Distribution 1 Review: Public Key Cryptography and RSA Cryptosystem Last lecture, we continued our discussion about public key cryptography. In a public key cryptosystem, there are two keys: a public encryption key, i.e., a key known to everyone and a private decryption key that is kept private and known only to a person whom a ciphertext was intended for. Under a public key cryptosystem, anyone can encrypt a message to send to Alice using her public key, PKA, but only Alice can decrypt the message using her private key SKA. The figure below presents a block diagram of a secure communication using public key cryptosystem. Plaintext Ciphertext Plaintext ENC CHANNEL Ciphertext DEC Bob Alice Public Private key PKA key SKA Fig. 1. Schematic of public key-based encryption and decryption. In this lecture, we will continue our discussion about the ElGamal cryptosystem. In doing so, let's first recall the definition of the discrete logarithm problem. 1.1 The Discrete Logarithm Problem Let's consider the set of integers modulo p, denoted as Zp. The set of integers in Zp that are relatively prime ? ? to p is denoted as Zp. As an example, when p = 13, Z13 = f1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12g. -
1 Review: Message Authentication Codes (Macs)
EE 418 Network Security and Cryptography Lecture #15 November 22, 2016 Message Authentication Codes (MACs). Digital Signatures. Lecture notes prepared by Professor Radha Poovendran. Tamara Bonaci Department of Electrical Engineering University of Washington, Seattle Outline: 1. Review: Message Authentication Codes (MACs) { Review: MAC from Block Cipher: CBC-MAC 2. Introduction to Digital Signatures 3. RSA digital signature scheme 4. ElGamal digital signature scheme 5. Schnoor Digital signature scheme 6. The Digital signature algorithm 1 Review: Message Authentication Codes (MACs) Last time, we started our discussion about message authentication codes (MACs), and we defined a MAC as a code that is appended to a message in order to provide message integrity1. In MACs, communicating parties share a secret key that is used to generate the code, and if a MAC is well-designed, then only a user with the shared key can compute a valid MAC for a given message. Two parties Alice and Bob who share a key K can use a MAC for message integrity as follows (illustrated in Figure 1): 1. Alice computes a MAC for message m as y = MAC(K; m), and sends pair (m; y) through the channel to Bob. 2. Bob receives (m; y). Using the secret key, Bob computes MAC(K; m) and checks y =? MAC(K; m). 3. If y = MAC(K; m), then Bob accepts the message. Otherwise, Bob rejects the message, since the message and MAC are inconsistent. Alice Bob MAC Generation Computes y = MAC(K,m) from secret key K and message m [m, y] MAC Verification Extracts m, computes y’=MAC(K,m) If y + y’ =0, accept the message If y + y’≠ 0, discard the message Fig. -
CE441: Data and Network Security Cryptography — Symmetric
CE441: Data and Network Security Cryptography — Symmetric Behnam Momeni, PhD Department of Computer Engineering Sharif University of Technology Fall 2019 . B. Momeni (Sharif Univ. of Tech.) CE441: Data and Network Security Fall 2019 1 / 94 Cryptology: Cryptography and Cryptanalysis Review: What Does Security Mean? Outline 1 Cryptology: Cryptography and Cryptanalysis Review: What Does Security Mean? Cryptography: Definition and Models Classic Cryptography Cryptanalysis: A Glimpse 2 Confidentiality-Providing Schemes 3 Integrity-Providing Schemes 4 Full Fledged Schemes . B. Momeni (Sharif Univ. of Tech.) CE441: Data and Network Security Fall 2019 2 / 94 Cryptology: Cryptography and Cryptanalysis Review: What Does Security Mean? Security Goals Availability CIA Triad Confidentiality Integrity . B. Momeni (Sharif Univ. of Tech.) CE441: Data and Network Security Fall 2019 3 / 94 Cryptology: Cryptography and Cryptanalysis Review: What Does Security Mean? Definition Defining an scheme has two main parts Syntax: specifies operations which can be performed by honest participants of the scheme e.g. The symmetric encryption scheme, SE = (K; E; D), contains a key generation function K, an encryption function E, and a decryption function D k K : 8m : Dk (Ek (m)) = m The scheme is modeled here Semantic: specifies conditions which must be met by a secure scheme The security definition is formalized here . B. Momeni (Sharif Univ. of Tech.) CE441: Data and Network Security Fall 2019 4 / 94 Cryptology: Cryptography and Cryptanalysis Review: What Does Security Mean? Game-based Definition Model the scheme operations normally Then, devise a game between an adversary and a challenger Adversary tries to break the security definition Challenger wants to demonstrate inability of the adversary Adversary is trying to obtain some advantage e.g. -
Security System on Data Encryption & Decryption
International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395-0056 Volume: 07 Issue: 04 | Apr 2020 www.irjet.net p-ISSN: 2395-0072 Security System on Data Encryption & Decryption Mr. Mukul Aggarwal1, Mr. Deepak Kumar Yadav2, Dr. Himanshu Arora3 and Mr. Sudhanshu Vashistha4 1B. Tech Student, Department of CSE, Arya College of Engineering and Research Center, Jaipur 2B. Tech Student, Department of CSE, Arya College of Engineering and Research Center, Jaipur 3Professor, Department of CSE, Arya College of Engineering and Research Center, Jaipur 4Assistant Professor, Department of CSE, Arya College of Engineering and Research Center, Jaipur ---------------------------------------------------------------------- ***--------------------------------------------------------- Abstract— Now’s a day’s security is a feature or factor which is most services attack. It is the attack in which third- person important about any sector which ensures the protection of data. It directly access the server. prevents unauthorized persons, thieves, hackers, etc. In this field, Access Control: It is the process in which only authorized there are three main feature which is essential for data security i.e. person can only access the data resources confidentiality, integrity, availability, these three main features which prevent from unauthorized any other third person. Confidentiality TABLE I basically if we send the data from one person to another person then FONT SIZES FOR PAPERS only authorized person can access & integrity if we transfer the information from one to another then no one can change. The availability of the resources should be available 24/7 hour or data should be available on demand. Process of communication using Encryption and Decryption over data. To convert the plain text into ciphertext is Encryption and convert the ciphertext into plain text is Decryption and both methods called as a Cryptology. -
Alice and Bob in Wonderland a First Glimpse in the World of Security and Cryptography
NXP SEMICONDUCTORS Alice and Bob in Wonderland A first glimpse in the world of security and cryptography September 2018 Mario Lamberger Agenda Introduction The Good The Bad The Ugly The Future COMPANY PUBLIC Introduction About myself MSc, PhD in technical mathematics, TU Graz Post-doc assistant at IAIK @ TU Graz – Java + network security, cryptography Habilitation in IT-Security @ IAIK/TU Graz 20+ publications in mathematics, cryptography, IT-security Principal Cryptographer and Security Assessment expert @ NXP – Joined 2011 – Works on crypto libraries, certification topics, analysis on random number generators – Lead of „NXP Security School“, trainings on cryptography, certification topics, implementation security Trained more than 2500 employees COMPANY PUBLIC THE GOOD Security in general COMPANY PUBLIC Key security requirements “Hello Confidentiality World” Integrity Keeping secrets Ensuring unmodified secret (business value data transport & “Hello “Hello of data, privacy – unmodified SW World” World” encryption is the execution technology of choice) Authenticity Alice Availability Verifying identities for Ensuring that the source of data/SW, “Fake” Bob services remain (trusted access control available operations) Bob “Fake” Alice COMPANY PUBLIC CONFIDENTIALITY Historic examples: This ... is ... Sparta! Scytale: – Oldest known military encryption scheme. – It was used by the Spartans already 2500 years ago to encrypt messages. – For encryption a wooden cylinder has been used with a certain diameter (acting as the key). The Scytale is a transposition cipher. Alternative hypothesis: Message authentication COMPANY PUBLIC Historic examples: Alea iacta est! Caesar cipher – The Caesar-Cipher is named after Julius Caesar (100-40 B.C.). – It was used for military correspondence. – For encryption the letters of the message where replaced by different letters of the same alphabet. -
When Encryption Is Not Enough Effective Concealment of Communication Pattern, Even Existence (Bitgrey, Bitloop)
When Encryption is Not Enough Effective Concealment of Communication Pattern, even Existence (BitGrey, BitLoop) Gideon Samid Department of Electrical Engineering and Computer Science Case Western Reserve University, Cleveland, OH [email protected] Abstract: How much we say, to whom, and when, is inherently telling, even if the contents of our communication is unclear. In other words: encryption is not enough; neither to secure privacy, nor to maintain confidentiality. Years ago Adi Shamir already predicted that encryption will be bypassed. And it has. The modern dweller of cyber space is routinely violated via her data behavior. Also, often an adversary has the power to compel release of cryptographic keys over well-exposed communication. The front has shifted, and now technology must build cryptographic shields beyond content, and into pattern, even as to existence of communication. We present here tools, solutions, methods to that end. They are based on equivocation. If a message is received by many recipients, it hides the intended one. If a protocol calls for decoy messages, then it protects the identity of the sender of the contents-laden message. BitGrey is a protocol that creates a "grey hole" (of various shades) around the communicating community, so that very little information leaks out. In addition the BitLoop protocol constructs a fixed rate circulating bit flow, traversing through all members of a group. The looping bits appear random, and effectively hide the pattern, even the existence of communication within the group. 1 Introduction We have fought for freedom in the physical world, and now the war moved to cyber space. -
Gartner Information Security Summit 2009 UK 21 September-22 September 2009
Summer is nearly over and we!re all getting back to our offices wondering how the holidays ended so quickly. To get you up and running with security insight, we bring you a collection of articles covering an assortment of themes, from cloud security to multi-enterprise application security. For us, just like for many of you, the next several months are going to be filled with a multitude of events spread worldwide. We!re going to cover BruCON in Belgium, RSA Conference in London and San Francisco, the Storage Expo in London, InfosecWorld in Orlando, just to name a few. If you!d like to arrange a meeting, bring us some products for review or just say hello, drop me a line. Mirko Zorz Editor in Chief Visit the magazine website at www.insecuremag.com (IN)SECURE Magazine contacts Feedback and contributions: Mirko Zorz, Editor in Chief - [email protected] News: Zeljka Zorz, News Editor - [email protected] Marketing: Berislav Kucan, Director of Marketing - [email protected] Distribution (IN)SECURE Magazine can be freely distributed in the form of the original, non modified PDF document. Distribution of modified versions of (IN)SECURE Magazine content is prohibited without the explicit permission from the editor. Copyright HNS Consulting Ltd. 2009. www.insecuremag.com VPN management for Linux networks NCP engineering released a new version of the software- based NCP Secure Enterprise Management System for Linux-based systems. Developed from the ground up to make hybrid IPSec / SSL networks powerful yet easy to manage, the system can plug-and-play with any existing network infrastructure or stand on its own as a new compo- nent. -
Arxiv:Quant-Ph/0601207V3 2 May 2006 Acmdtraid Atcooi,Ad.Cnlol´Impic, S/ Canal Avda
E. WOLF, PROGRESS IN OPTICS VVV c 199X ALL RIGHTS RESERVED X QUANTUM CRYPTOGRAPHY BY Miloslav Duˇsek Department of Optics, Palack´yUniversity 17. listopadu 50, 77200 Olomouc, Czech Republic Norbert Lutkenhaus¨ Institut f¨ur Optik, Information und Photonik Universit¨at Erlangen-N¨urnberg Staudtstr. 7/B3, 91058 Erlangen, Germany Martin Hendrych ICFO - Institut de Ci`encies Fot`oniques Parc Mediterrani de la Tecnologia, Avda. Canal Ol´ımpic, s/n 08860 Castelldefels (Barcelona), Spain arXiv:quant-ph/0601207v3 2 May 2006 1 CONTENTS1 PAGE 1. CIPHERING 3 § 2. QUANTUM KEY DISTRIBUTION 9 § 3. SOMEOTHERDISCRETEPROTOCOLSFORQKD 14 § 4. EXPERIMENTS 18 § 5. TECHNOLOGY 26 § 6. LIMITATIONS 34 § 7. SUPPORTING PROCEDURES 35 § 8. SECURITY 38 § 9. PROSPECTS 51 REFERENCES§ 52 1Run LaTeX twice for up-to-date contents. 2 1. CIPHERING 3 1. Ciphering §§§ 1.1. INTRODUCTION, CRYPTOGRAPHIC TASKS There is no doubt that electronic communications have become one of the main pillars of the modern society and their ongoing boom requires the development of new methods and techniques to secure data transmission and data storage. This is the goal of cryptography. Etymologically derived from Greek κρυπτoς´ , hidden or secret, and γραϕη´, writing, cryptography may generally be defined as the art of writing (encryption) and deciphering (decryption) messages in code in order to ensure their confidentiality, authenticity, integrity and non-repudiation. Cryptog- raphy and cryptanalysis, the art of codebreaking, together constitute cryptology (λoγoς´ , a word). Nowadays many paper-based communications have already been replaced by elec- tronic means, raising the challenge to find electronic counterparts to stamps, seals and hand-written signatures. The growing variety of applications brings many tasks that must be solved.