Cryptology is the art and science of secure communication over insecure channels. The primary aim of this book is to provide a self-contained overview of recent cryptologic achievements and techniques in a form that can be understood by readers having no previous acquaintance with cryptology. It can thus be used as independent reading by whoever wishes to get started on the subject. An extensive bibliography of 250 references is included to help the reader deepen his or her understanding and go beyond the topics treated here. This book can also be used as preliminary material for an introductory course on cryptology. Despite its simplicity, it covers enough state-of-the-art material to be nevertheless of interest to the specialist. After a survey of the main secret and public key techniques, various applications are discussed. The last chapter describes 'quantum cryptography', a revolutionary approach to cryptography that remains secure even against an opponent with unlimited computing power. Quantum crytography is based on the principles of quantum physics.

This book concerns digital communication. Specifically, we treat the transport of bit streams from one geographical location to another over various physical media, such as wire pairs, coaxial cable, optical fiber, and radio waves. Further, we cover the mul tiplexing, multiple access, and synchronization issues relevant to constructing com munication networks that simultaneously transport bit streams from many users. The material in this book is thus directly relevant to the design of a multitude of digital communication systems, including for example local and metropolitan area data net works, voice and video telephony systems, the integrated services digital network (ISDN), computer communication systems, voiceband data modems, and satellite communication systems. We extract the common principles underlying these and other applications and present them in a unified framework. This book is intended for designers and would-be designers of digital communication systems. To limit the scope to manageable proportions we have had to be selective in the topics covered and in the depth of coverage. In the case of advanced information, coding, and detection theory, for example, we have not tried to duplicate the in-depth coverage of many advanced textbooks, but rather have tried to cover those aspects directly relevant to the design of digital communication systems."

This book contains a selection of papers presented at a Symposium on coding theory: "3 Journ es sur le Codage," held November 24-26, 1986, in Cachan near Paris, France. It gives an account of the state of the art of research in France on Coding, ranging from rather theoretical topics like algebraic geometry and combinatorial coding to applications like modulation, real-space decoding and implementation of coding algorithms on microcomputers. The symposium was the second one of this type. With its broad spectrum, it was a unique opportunity for contacts between university and industry on the topics of information and coding theory.

This book is the proceedings of CRYPTO 86, one in a series of annual conferences devoted to cryptologic research. They have all been held at the University of California at Santa Barbara. The first conference in this series, CRYPTO 81, organized by A. Gersho, did not have a formal proceedings. The proceedings of the following four conferences in this series have been published as: Advances in Cryptology: Proceedings of Crypto 82, D. Chaum, R. L. Rivest, and A. T. Sherman, eds., Plenum, 1983. Advances in Cryptology: Proceedings of Crypto 83, D. Chaum, ed., Plenum, 1984. Advances in Cryptology: Proceedings of CRYPTO 84, G. R. Blakley and D. Chaum, eds., Lecture Notes in Computer Science #196, Springer, 1985. Advances in Cryptology - CRYPTO '85 Proceedings, H. C. Williams, ed., Lecture Notes in Computer Science #218, Springer, 1986. A parallel series of conferences is held annually in Europe. The first of these had its proceedings published as Cryptography: Proceedings, Burg Feuerstein 1982, T. Beth, ed., Lecture Notes in Computer Science #149, Springer, 1983.

This book contains the proceedings of EUROCRYPT 85, held in Paris in 1984, April 9-11, at the University of Paris, Sorbonne. EIJROCRYPT is now an annual international European meeting in cryptology, intended primarily for the international of researchers in this area. EUROCRYPT 84 was community following previous meetings held at Burg Feuerstein in 1982 and at IJdine in 1983. In fact EUROCRYPT 84 was thc first such meeting being organized under IXCR (International Association of Cryptology Research). Other sponsors were the well-known French association on cybernetics research AFCET, the LITP (Laborstoire d' Informntique thcorique called et de Programmation), which is a laboratory of computer science associated with CNRS, and the department of mathematics and computer science at the Ilniversity RenE Descartcs, Sorbonne. EUROCRYPT 83 was very successfull, with about 180 participants from a great variety of foreign countries and 50 papers addressing all aspects of cryptology, close to applied as well as theoretical. It also had a special feature, i.e. a special session on smart cards particularly welcome at the time, since France was then carrying on an ambitious program on smart cards. EUROCRYPT 84 was a great experience. We like to thank all the sponsors and all the authors for their submission of papers. Pakin, Decemben 74ti4. CONTENTS SECTION I: GENERAL THEORY, CLASSICAL METHODS 3 Cryptology and Complexity Theories ............................ G. RLiGGTU 1 0 On Cryptosystems based on Folynomials md I'inite Fields.. ..... R. irvi 16 Algehraical Structures of Cryptographic lransformations.. .....

Der Arbeitskreis "Datenschutz und Datensicherung" des Prasidiums der Gesellschaft fur In- formatik sieht es als seine Aufgabe an, Probleme des Datenschutzes und der Datensicherung aus der Sicht der Informatik zu behandeln. Er hat in diesem Rahmen grundsatzliche Aus- sagen zu diesen Themen unter besonderer Berucksichtigung der sich rasch entwickelnden In- formationstechnologien erarbeitet und zu Entwurfen fur Anderungen des Bundesdatenschutz- gesetzes Stellung genommen. Aus dieser Tatigkeit heraus entstand der Plan zur Durchfuh- rung einer Fachtagung mit dem Thema "Datenschutz und Datensicherung im Wandel der Informationstechnologien". Diese Tagung, deren Beitrage dieser Band enthalt, findet am 30. und 31. Oktober 1985 im Rahmen der SYSTEMS 85 statt. Sie soll die Datenschutz- und Datensicherungs-Probleme, die mit den wachsenden technologischen Moglichkeiten entstehen, aus der Sicht der Informa- tionstechnik beleuchten. Sie soll Methoden, Verfahren und Hilfsmittel aufzeigen, mit denen die Datenschutz- und Datensicherungs-Probleme konstruktiv einer Losung naher gebracht werden konnen. Sie soll Anwender von Rechensystemen und Kommunikationsnetzen, Juristen und Informatiker dazu anregen, gemeinsam uber Datenschutz- und Datensicherungs-Probleme nachzudenken und miteinander Losungen dieser Probleme zu erarbeiten.

Recently, there has been a lot of interest in provably "good" pseudo-random number generators [lo, 4, 14, 31. These cryptographically secure generators are "good" in the sense that they pass all probabilistic polynomial time statistical tests. However, despite these nice properties, the secure generators known so far suffer from the han- cap of being inefiicient; the most efiicient of these take n2 steps (one modular multip- cation, n being the length of the seed) to generate one bit. Pseudc-random number g- erators that are currently used in practice output n bits per multiplication (n2 steps). An important open problem was to output even two bits on each multiplication in a cryptographically secure way. This problem was stated by Blum, Blum & Shub [3] in the context of their z2 mod N generator. They further ask: how many bits can be o- put per multiplication, maintaining cryptographic security? In this paper we state a simple condition, the XOR-Condition and show that any generator satisfying this condition can output logn bits on each multiplication. We show that the XOR-Condition is satisfied by the lop least significant bits of the z2-mod N generator. The security of the z2 mod N generator was based on Quadratic Residu- ity [3]. This generator is an example of a Trapdoor Generator [13], and its trapdoor properties have been used in protocol design. We strengthen the security of this gene- tor by proving it as hard as factoring.

T. Beth (Ed.): Cryptography - EUROCRYPT '82, LNCS 149, pp. 1-28, 1983. 0 Springer-Verlag Berlin Heidelberg 1983 3 Having all of a sudden left the shady corner of semi-military art, modern cryptography has become a central topic of research in all areas of communication science. Definitions (cf. Bauer pp. 31 - 48) Cryptographic measures are applied to p- tect valuable data during transmission against unwanted interception INTERCEPTOR Fig. A: passive violation and (possibly undectable) forgery . Fig. 2: acti-se violation In accordance with the subsequent paper of Bauer (pp. 31 - 481, the technique applied to meet these requirements is called en- tion. In this process the transmitter enciphers (or encrypts) a plaintext message into a ciphertext. 4 ciphertexc ciphering Fig. 3: The Wire-tap-channel This transformation is called a cipher(function) which the au- rized receiver deciphers (decrypts). An enemy is a person or institution who wants illegal access to the messages. Assuming that the enemy can only get hold of the ciph- texts, he has to perform a cryptanalysis in order to reconstitute the plaintexts. To add to the difficulties for a cryptanalyst, the cipher functions are chosen to a varying parameter, called the key. A generator cryptosystem consists of a class of injective cipher functions ES: M-C, mapping plaintext messages(EM) into ciphertexts(EC) . The parameter s runs through the set K of keys. These formulations are best demonstrated by the basic, classical examples.

Building on the success of the first edition, An Introduction to Number Theory with Cryptography, Second Edition, increases coverage of the popular and important topic of cryptography, integrating it with traditional topics in number theory. The authors have written the text in an engaging style to reflect number theory's increasing popularity. The book is designed to be used by sophomore, junior, and senior undergraduates, but it is also accessible to advanced high school students and is appropriate for independent study. It includes a few more advanced topics for students who wish to explore beyond the traditional curriculum. Features of the second edition include Over 800 exercises, projects, and computer explorations Increased coverage of cryptography, including Vigenere, Stream, Transposition,and Block ciphers, along with RSA and discrete log-based systems "Check Your Understanding" questions for instant feedback to students New Appendices on "What is a proof?" and on Matrices Select basic (pre-RSA) cryptography now placed in an earlier chapter so that the topic can be covered right after the basic material on congruences Answers and hints for odd-numbered problems About the Authors: Jim Kraft received his Ph.D. from the University of Maryland in 1987 and has published several research papers in algebraic number theory. His previous teaching positions include the University of Rochester, St. Mary's College of California, and Ithaca College, and he has also worked in communications security. Dr. Kraft currently teaches mathematics at the Gilman School. Larry Washington received his Ph.D. from Princeton University in 1974 and has published extensively in number theory, including books on cryptography (with Wade Trappe), cyclotomic fields, and elliptic curves. Dr. Washington is currently Professor of Mathematics and Distinguished Scholar-Teacher at the University of Maryland.

This book provides basic concepts and deep knowledge about various security mechanisms that can be implemented in IoT through Blockchain technology. This book aids readers in gaining insight and knowledge about providing security and solutions to different challenges in IoT using Blockchain technology. This book primarily focuses on challenges to addressing the integration of the IoT with Blockchain with respect to potential benefits for IoT. This book gives descriptive analysis of Blockchain integrated with IoT applications and platforms for the development of IoT solutions along with possible topologies to that integration. Several application examples are included in a variety of industries.

Blockchain is an emerging technology platform for developing decentralized applications and data storage, over and beyond its role as the technology underlying the cryptocurrencies. The basic tenet of this platform is that it allows one to create a distributed and replicated ledger of events, transactions, and data generated through various IT processes with strong cryptographic guarantees of tamper resistance, immutability, and verifiability. Public blockchain platforms allow us to guarantee these properties with overwhelming probabilities even when untrusted users are participants of distributed applications with the ability to transact on the platform. Even though, blockchain technology has become popularly known because of its use in the implementation of cryptocurrencies such as BitCoin, Ethereum, etc.; the technology itself holds much more promise in various areas such as time stamping, logging of critical events in a system, recording of transactions, trustworthy e-governance, etc. It introduces theoretical and practical aspects of blockchain technology. The book includes an in-depth insight into the need for decentralization, smart contracts, consensus both permissioned and permissionless, and various blockchain development frameworks, tools, and platforms. It can be used as a learning resource for various examinations and certifications related to cryptocurrency and blockchain technology. This book explained the nuts and bolts of blockchain technology in lucid language to make students more familiar with the implementation perspective of this much-needed technology.

Modern cryptography has evolved dramatically since the 1970s. With the rise of new network architectures and services, the field encompasses much more than traditional communication where each side is of a single user. It also covers emerging communication where at least one side is of multiple users. New Directions of Modern Cryptography presents general principles and application paradigms critical to the future of this field. The study of cryptography is motivated by and driven forward by security requirements. All the new directions of modern cryptography, including proxy re-cryptography, attribute-based cryptography, batch cryptography, and noncommutative cryptography have arisen from these requirements. Focusing on these four kinds of cryptography, this volume presents the fundamental definitions, precise assumptions, and rigorous security proofs of cryptographic primitives and related protocols. It also describes how they originated from security requirements and how they are applied. The book provides vivid demonstrations of how modern cryptographic techniques can be used to solve security problems. The applications cover wired and wireless communication networks, satellite communication networks, multicast/broadcast and TV networks, and newly emerging networks. It also describes some open problems that challenge the new directions of modern cryptography. This volume is an essential resource for cryptographers and practitioners of network security, security researchers and engineers, and those responsible for designing and developing secure network systems.

This two volume set (CCIS 1451 and 1452) constitutes the refereed proceedings of the 7th International Conference of Pioneering Computer Scientists, Engineers and Educators, ICPCSEE 2021 held in Taiyuan, China, in September 2021.The 81 papers presented in these two volumes were carefully reviewed and selected from 256 submissions. The papers are organized in topical sections on big data management and applications; social media and recommendation systems; infrastructure for data science; basic theory and techniques for data science; machine learning for data science; multimedia data management and analysis; social media and recommendation systems; data security and privacy; applications of data science; education research, methods and materials for data science and engineering; research demo.

"Blockchains will matter crucially; this book, beautifully and clearly written for a wide audience, powerfully demonstrates how." -Lawrence Lessig "Attempts to do for blockchain what the likes of Lawrence Lessig and Tim Wu did for the Internet and cyberspace-explain how a new technology will upend the current legal and social order... Blockchain and the Law is not just a theoretical guide. It's also a moral one." -Fortune Bitcoin has been hailed as an Internet marvel and decried as the preferred transaction vehicle for criminals. It has left nearly everyone without a computer science degree confused: how do you "mine" money from ones and zeros? The answer lies in a technology called blockchain. A general-purpose tool for creating secure, decentralized, peer-to-peer applications, blockchain technology has been compared to the Internet in both form and impact. Blockchains are being used to create "smart contracts," to expedite payments, to make financial instruments, to organize the exchange of data and information, and to facilitate interactions between humans and machines. But by cutting out the middlemen, they run the risk of undermining governmental authorities' ability to supervise activities in banking, commerce, and the law. As this essential book makes clear, the technology cannot be harnessed productively without new rules and new approaches to legal thinking. "If you...don't 'get' crypto, this is the book-length treatment for you." -Tyler Cowen, Marginal Revolution "De Filippi and Wright stress that because blockchain is essentially autonomous, it is inflexible, which leaves it vulnerable, once it has been set in motion, to the sort of unforeseen consequences that laws and regulations are best able to address." -James Ryerson, New York Times Book Review

Seit der Begriindung der Informations- und Codierungstheorie durch die Ar beiten von Claude E. Shannon sind fast fiinf Jahrzehnte vergangen. In diesem Zeitraum hat sich die Kanalcodierung von einer rein theoretischen Disziplin zu einer ausgedehnten anwendungsorientierten Wissenschaft entwickelt. In fast allen modernen und leistungsfahigen Systemen zur Nachrichteniibertragung oder Nachrichtenspeicherung stellt die Kanalcodierung heute einen zentralen und pragenden Baustein dar. Mit der Compact Disc und mit Modems zur Dateniibertragung dringen Codierungsverfahren inzwischen auch in die privat genutzte Elektronik vor. Durch Kanalcodierung kann die Ubertragungsqualitat enorm gesteigert werden und gleichzeitig kommen die Ubertragungsverfahren mit weniger Sen deleistung und teilweise auch mit weniger Bandbreite aus. Diese Vorteile miissen nicht mit einer Reduktion der Datenrate bezahlt werden, sondern nur mit einem erh6hten Aufwand an digitaler Signalverarbeitung in Sender und Empfanger. Die Codierungstheorie liefert Resultate zur Struktur und zu den Eigenschaften von Codes sowie effiziente und aufwandsgiinstige Verfahren zur Decodierung. Zusammen mit der hochintegrierten Schaltungstechnik, die im mer leistungsfahiger und kostengiinstiger wird, fiihren die Fortschritte in der Kanalcodierung zu einer standigen Weiterentwicklung der Ubertragungsver fahren sowie zu einer effizienteren Nutzung der UbertragungskanaIe."

This open access book covers the most cutting-edge and hot research topics and fields of post-quantum cryptography. The main purpose of this book is to focus on the computational complexity theory of lattice ciphers, especially the reduction principle of Ajtai, in order to fill the gap that post-quantum ciphers focus on the implementation of encryption and decryption algorithms, but the theoretical proof is insufficient. In Chapter 3, Chapter 4 and Chapter 6, author introduces the theory and technology of LWE distribution, LWE cipher and homomorphic encryption in detail. When using random analysis tools, there is a problem of "ambiguity" in both definition and algorithm. The greatest feature of this book is to use probability distribution to carry out rigorous mathematical definition and mathematical demonstration for various unclear or imprecise expressions, so as to make it a rigorous theoretical system for classroom teaching and dissemination. Chapters 5 and 7 further expand and improve the theory of cyclic lattice, ideal lattice and generalized NTRU cryptography. This book is used as a professional book for graduate students majoring in mathematics and cryptography, as well as a reference book for scientific and technological personnel engaged in cryptography research.

In the age of data-driven problem-solving, applying sophisticated computational tools for explaining substantive phenomena is a valuable skill. Yet, application of methods assumes an understanding of the data, structure, and patterns that influence the broader research program. This Element offers researchers and teachers an introduction to clustering, which is a prominent class of unsupervised machine learning for exploring and understanding latent, non-random structure in data. A suite of widely used clustering techniques is covered in this Element, in addition to R code and real data to facilitate interaction with the concepts. Upon setting the stage for clustering, the following algorithms are detailed: agglomerative hierarchical clustering, k-means clustering, Gaussian mixture models, and at a higher-level, fuzzy C-means clustering, DBSCAN, and partitioning around medoids (k-medoids) clustering.

Data structures and algorithms are presented at the college level in a highly accessible format that presents material with one-page displays in a way that will appeal to both teachers and students. The thirteen chapters cover: Models of Computation, Lists, Induction and Recursion, Trees, Algorithm Design, Hashing, Heaps, Balanced Trees, Sets Over a Small Universe, Graphs, Strings, Discrete Fourier Transform, Parallel Computation. Key features: Complicated concepts are expressed clearly in a single page with minimal notation and without the "clutter" of the syntax of a particular programming language; algorithms are presented with self-explanatory "pseudo-code." * Chapters 1-4 focus on elementary concepts, the exposition unfolding at a slower pace. Sample exercises with solutions are provided. Sections that may be skipped for an introductory course are starred. Requires only some basic mathematics background and some computer programming experience. * Chapters 5-13 progress at a faster pace. The material is suitable for undergraduates or first-year graduates who need only review Chapters 1 -4. * This book may be used for a one-semester introductory course (based on Chapters 1-4 and portions of the chapters on algorithm design, hashing, and graph algorithms) and for a one-semester advanced course that starts at Chapter 5. A year-long course may be based on the entire book. * Sorting, often perceived as rather technical, is not treated as a separate chapter, but is used in many examples (including bubble sort, merge sort, tree sort, heap sort, quick sort, and several parallel algorithms). Also, lower bounds on sorting by comparisons are included with the presentation of heaps in the context of lower bounds for comparison-based structures. * Chapter 13 on parallel models of computation is something of a mini-book itself, and a good way to end a course. Although it is not clear what parallel

The humanities and social sciences are interested in the cybersecurity object since its emergence in the security debates, at the beginning of the 2000s. This scientific production is thus still relatively young, but diversified, mobilizing at the same time political science, international relations, sociology, law, information science, security studies, surveillance studies, strategic studies, polemology. There is, however, no actual cybersecurity studies. After two decades of scientific production on this subject, we thought it essential to take stock of the research methods that could be mobilized, imagined and invented by the researchers. The research methodology on the subject "cybersecurity" has, paradoxically, been the subject of relatively few publications to date. This dimension is essential. It is the initial phase by which any researcher, seasoned or young doctoral student, must pass, to define his subject of study, delimit the contours, ask the research questions, and choose the methods of treatment. It is this methodological dimension that our book proposes to treat. The questions the authors were asked to answer were: how can cybersecurity be defined? What disciplines in the humanities and social sciences are studying, and how, cybersecurity? What is the place of pluralism or interdisciplinarity? How are the research topics chosen, the questions defined? How, concretely, to study cybersecurity: tools, methods, theories, organization of research, research fields, data ...? How are discipline-specific theories useful for understanding and studying cybersecurity? Has cybersecurity had an impact on scientific theories?

In this Element and its accompanying second Element, A Practical Introduction to Regression Discontinuity Designs: Extensions, Matias Cattaneo, Nicolas Idrobo, and Rociio Titiunik provide an accessible and practical guide for the analysis and interpretation of regression discontinuity (RD) designs that encourages the use of a common set of practices and facilitates the accumulation of RD-based empirical evidence. In this Element, the authors discuss the foundations of the canonical Sharp RD design, which has the following features: (i) the score is continuously distributed and has only one dimension, (ii) there is only one cutoff, and (iii) compliance with the treatment assignment is perfect. In the second Element, the authors discuss practical and conceptual extensions to this basic RD setup.

The book is a collection of best selected research papers presented at International Conference on Network Security and Blockchain Technology (ICNSBT 2021), organized by Computer Society of India-Kolkata Chapter, India, during December 2-4, 2021. The book discusses recent developments and contemporary research in cryptography, network security, cyber security, and blockchain technology. Authors are eminent academicians, scientists, researchers, and scholars in their respective fields from across the world.