Asiacrypt’99 was held in Singapore on 14-18 November 1999. Asiacrypt is one of the major events in the cryptology research community. Asiacrypt’99, the ?fth annual Asiacrypt conference, was sponsored by the Asiacrypt Steering Comm- tee and the Centre for Systems Security of the National University of Singapore, and in cooperation with the International Association for Cryptology Research. As the Program Co-Chairs of Asiacrypt’99, we are extremely honored to or- nize this event, which showcases the state-of-the-art development of cryptology research at the conclusion of this millennium. This year, a total of 96 research papers were submitted to Asiacrypt’99. The portfolio of country of origin of submissions serves as a good indicator of the - ternational reputation of the conference. Countries from which submissions or- inated include: Australia, Belgium, China, Estonia, France, Germany, Greece, India, Iran, Japan, Korea, Norway, Russia, Saudi Arabia, Switzerland, Sin- pore, Spain, Taiwan, Thailand, The Netherlands, Turkey, Ukraine, UK, USA and Yugoslavia. Through a stringent refereeing process by the Program C- mittee, 31 papers of outstanding quality were accepted and are included in the conference proceedings. Accepted papers were authored by researchers from the following countries: Australia, Belgium, France, Germany, India, Japan, China, Singapore, Switzerland, Taiwan, The Netherlands, UK, and USA.

ASIACRYPT 2000 was the sixth annual ASIACRYPT conference. It was sp- sored by the International Association for Cryptologic Research (IACR) in - operation with the Institute of Electronics, Information, and Communication Engineers (IEICE). The ?rst conference with the name ASIACRYPT took place in 1991, and the series of ASIACRYPT conferences were held in 1994, 1996, 1998, and 1999, in cooperation with IACR. ASIACRYPT 2000 was the ?rst conference in the series to be sponsored by IACR. The conference received 140 submissions (1 submission was withdrawn by the authors later), and the program committee selected 45 of these for presen- tion. Extended abstracts of the revised versions of these papers are included in these proceedings. The program also included two invited lectures by Thomas Berson (Cryptography Everywhere: IACR Distinguished Lecture) and Hideki Imai (CRYPTREC Project – Cryptographic Evaluation Project for the Japanese Electronic Government). Abstracts of these talks are included in these proce- ings. The conference program also included its traditional “rump session” of short, informal or impromptu presentations, kindly chaired by Moti Yung. Those p- sentations are not re?ected in these proceedings. The selection of the program was a challenging task as many high quality submissions were received. The program committee worked very hard to evaluate the papers with respect to quality, originality, and relevance to cryptography. I am extremely grateful to the program committee members for their en- mous investment of time and e?ort in the di?cult and delicate process of review and selection.

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.

This book constitutes the refereed proceedings of the 20th Annual International Cryptology Conference, CRYPTO 2000, held in Santa Barbara, CA, USA in August 2000. The 32 revised full papers presented together with one invited contribution were carefully reviewed and selected from 120 submissions. The papers are organized in topical sections on XTR and NTRU, privacy for databases, secure distributed computation, algebraic cryptosystems, message authentication, digital signatures, cryptanalysis, traitor tracing and broadcast encryption, symmetric encryption, to commit or not to commit, protocols, and stream ciphers and Boolean functions.

This book constitutes the thoroughly refereed post-proceedings of the Second International Conference on Information Security and Cryptology, ICISC'99, held in Seoul, Korea, in December 1999. The 20 revised full papers presented together with an invited paper were carefully reviewed and selected from a total of 61 submissions. The book is divided into topical sections on cryptoanalysis and cryptographic design; cryptographic theory and computation complexity; cryptographic protocols and authentication design; digital signatures and secret sharing; and electronic cash, applications, and implementation.

Crypto 2003, the 23rd 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 169 submissions, of which the program committee selected 34 for presentation. These proceedings contain the revised versions of the 34 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. Submissions to the conference represent cutti- edge research in the cryptographic community worldwide and cover all areas of cryptography. Many high-quality works could not be accepted. These works will surely be published elsewhere. The conference program included two invited lectures. Moni Naor spoke on cryptographic assumptions and challenges. Hugo Krawczyk spoke on the ‘SI- and-MAc’approachtoauthenticatedDi?e-HellmananditsuseintheIKEpro- cols. The conference program also included the traditional rump session, chaired by Stuart Haber, featuring short, informal talks on late-breaking research news. Assembling the conference program requires the help of many many people. To all those who pitched in, I am forever in your debt. I would like to ?rst thank the many researchers from all over the world who submitted their work to this conference. Without them, Crypto could not exist. I thank Greg Rose, the general chair, for shielding me from innumerable logistical headaches, and showing great generosity in supporting my e?orts.

Algorithmic number theory is a rapidly developing branch of number theory, which, in addition to its mathematical importance, has substantial applications in computer science and cryptography. Among the algorithms used in cryptography, the following are especially important: algorithms for primality testing; factorization algorithms for integers and for polynomials in one variable; applications of the theory of elliptic curves; algorithms for computation of discrete logarithms; algorithms for solving linear equations over finite fields; and, algorithms for performing arithmetic operations on large integers. The book describes the current state of these and some other algorithms. It also contains extensive bibliography. For this English translation, additional references were prepared and commented on by the author.

This book constitutes the refereed proceedings of the 8th Australasian Conference on Information Security and Privacy, ACISP 2003, held in Wollongong, Australia, in July 2003. The 42 revised full papers presented together with 3 invited contributions were carefully reviewed and selected from 158 submissions. The papers are organized in topical sections on privacy and anonymity, elliptic curve cryptography, cryptanalysis, mobile and network security, digital signatures, cryptosystems, key management, and theory and hash functions.

This book constitutes the thoroughly refereed post-proceedings of the 11th International Workshop on Selected Areas in Cryptography, SAC 2004, held in Waterloo, Canada in August 2004. The 24 revised full papers presented were carefully selected during two rounds of reviewing and improvement. The papers are organized in topical sections on stream cipher analysis, side channel analysis, block cipher design, efficient implementations, secret key cryptography, cryptanalysis, and cryptographic protocols.