Protocols that remain zero-knowledge when many instances are executed concurrently are called concurrent zero-knowledge, and this book is devoted to their study. The book presents constructions of concurrent zero-knowledge protocols, along with proofs of security. It also shows why "traditional" proof techniques (i.e., black-box simulation) are not suitable for establishing the concurrent zero-knowledge property of "message-efficient" protocols.

Crypto 2001, the 21st Annual Crypto conference, was sponsored by the Int- national Association for Cryptologic Research (IACR) in cooperation with the IEEE Computer Society Technical Committee on Security and Privacy and the Computer Science Department of the University of California at Santa Barbara. The conference received 156 submissions, of which the program committee selected 34 for presentation; one was later withdrawn. These proceedings contain the revised versions of the 33 submissions that were presented at the conference. These revisions have not been checked for correctness, and the authors bear full responsibility for the contents of their papers. The conference program included two invited lectures. Mark Sherwin spoke on, \Quantum information processing in semiconductors: an experimentalist’s view." Daniel Weitzner spoke on, \Privacy, Authentication & Identity: A recent history of cryptographic struggles for freedom." The conference program also included its perennial \rump session," chaired by Stuart Haber, featuring short, informal talks on late{breaking research news. As I try to account for the hours of my life that ?ew o to oblivion, I realize that most of my time was spent cajoling talented innocents into spending even more time on my behalf. I have accumulated more debts than I can ever hope to repay. As mere statements of thanks are certainly insu cient, consider the rest of this preface my version of Chapter 11.

Cryptography is concerned with the construction of schemes that withstand any abuse. A cryptographic scheme is constructed so as to maintain a desired functionality, even under malicious attempts aimed at making it deviate from its prescribed behavior. The design of cryptographic systems must be based on firm foundations, whereas ad hoc approaches and heuristics are a very dangerous way to go. These foundations were developed mostly in the 1980s, in works that are all co-authored by Shafi Goldwasser and/or Silvio Micali. These works have transformed cryptography from an engineering discipline, lacking sound theoretical foundations, into a scientific field possessing a well-founded theory, which influences practice as well as contributes to other areas of theoretical computer science. This book celebrates these works, which were the basis for bestowing the 2012 A.M. Turing Award upon Shafi Goldwasser and Silvio Micali. A significant portion of this book reproduces some of these works, and another portion consists of scientific perspectives by some of their former students. The highlight of the book is provided by a few chapters that allow the readers to meet Shafi and Silvio in person. These include interviews with them, their biographies and their Turing Award lectures.

A multi-user game, web site, cloud application, or networked database can have thousands of users all interacting at the same time. You need a powerful, industrial-strength tool to handle the really hard problems inherent in parallel, concurrent environments. You need Erlang. In this second edition of the bestselling Programming Erlang, you'll learn how to write parallel programs that scale effortlessly on multicore systems. Using Erlang, you'll be surprised at how easy it becomes to deal with parallel problems, and how much faster and more efficiently your programs run. That's because Erlang uses sets of parallel processes-not a single sequential process, as found in most programming languages. Joe Armstrong, creator of Erlang, introduces this powerful language in small steps, giving you a complete overview of Erlang and how to use it in common scenarios. You'll start with sequential programming, move to parallel programming and handling errors in parallel programs, and learn to work confidently with distributed programming and the standard Erlang/Open Telecom Platform (OTP) frameworks. You need no previous knowledge of functional or parallel programming. The chapters are packed with hands-on, real-world tutorial examples and insider tips and advice, and finish with exercises for both beginning and advanced users. The second edition has been extensively rewritten. New to this edition are seven chapters covering the latest Erlang features: maps, the type system and the Dialyzer, WebSockets, programming idioms, and a new stand-alone execution environment. You'll write programs that dynamically detect and correct errors, and that can be upgraded without stopping the system. There's also coverage of rebar (the de facto Erlang build system), and information on how to share and use Erlang projects on github, illustrated with examples from cowboy and bitcask. Erlang will change your view of the world, and of how you program. What You Need The Erlang/OTP system. Download it from erlang.org.

This book constitutes the refereed proceedings of the 18th International Conference on the Theory and Application of Cryptology and Information Security, Asiacrypt 2012, held in Beijing, China, in December 2012. The 43 full papers presented were carefully reviewed and selected from 241 submissions. They are organized in topical sections named: public-key cryptography, foundation, symmetric cipher, security proof, lattice-based cryptography and number theory, hash function, cryptographic protocol, and implementation issues.

This book is devoted to the most difficult part of concurrent programming, namely synchronization concepts, techniques and principles when the cooperating entities are asynchronous, communicate through a shared memory, and may experience failures. Synchronization is no longer a set of tricks but, due to research results in recent decades, it relies today on sane scientific foundations as explained in this book. In this book the author explains synchronization and the implementation of concurrent objects, presenting in a uniform and comprehensive way the major theoretical and practical results of the past 30 years. Among the key features of the book are a new look at lock-based synchronization (mutual exclusion, semaphores, monitors, path expressions); an introduction to the atomicity consistency criterion and its properties and a specific chapter on transactional memory; an introduction to mutex-freedom and associated progress conditions such as obstruction-freedom and wait-freedom; a presentation of Lamport's hierarchy of safe, regular and atomic registers and associated wait-free constructions; a description of numerous wait-free constructions of concurrent objects (queues, stacks, weak counters, snapshot objects, renaming objects, etc.); a presentation of the computability power of concurrent objects including the notions of universal construction, consensus number and the associated Herlihy's hierarchy; and a survey of failure detector-based constructions of consensus objects. The book is suitable for advanced undergraduate students and graduate students in computer science or computer engineering, graduate students in mathematics interested in the foundations of process synchronization, and practitioners and engineers who need to produce correct concurrent software. The reader should have a basic knowledge of algorithms and operating systems.

A zero-knowledge proof of knowledge allows one party to convince another party that it knows a secret piece of information without revealing anything about it. Such protocols are important building blocks for many interesting higher-level cryptographic applications, such as e-voting and e-cash systems, digital signature and identification schemes, or anonymous credential systems. Unfortunately, their high computational costs, as well as long and error-prone implementation cycles, are major hurdles on their way to real-world usage. This thesis contributes to overcoming these restrictions. On the practical side, we introduce a compiler which automatically translates natural specifications of zero-knowledge proofs into concrete implementations. In addition, it generates formal proofs that the generated protocols are indeed sound. On the theoretical side, we analyze inherent efficiency limitations of igma-protocols, proving the optimality of currently known protocols. Finally, we consider zero-knowledge proofs in the Universal Composability framework. By enabling UC-compliant proofs of existence for the first time, we are able to decrease the computational complexity of many practically relevant UC-secure zero-knowledge protocols to an acceptable level.