The aim of this text is to treat selected topics of the subject of contemporary cryptology, structured in five quite independent but related themes:
- efficient distributed computation modulo a shared secret
- multiparty computation
- foundations of modern cryptography
- provable security for public key schemes
- efficient and secure public-key cryptosystems.

This book constitutes the refereed proceedings of the 31st Annual International Conference on the Theory and Applications of Cryptographic Techniques, EUROCRYPT 2012, held in Cambgridge, UK, in April 2012. The 41 papers, presented together with 2 invited talks, were carefully reviewed and selected from 195 submissions. The papers are organized in topical sections on index calculus, symmetric constructions, secure computation, protocols, lossy trapdoor functions, tools, symmetric cryptanalysis, fully homomorphic encryption, asymmetric cryptanalysis, efficient reductions, public-key schemes, security models, and lattices.

The 13th International Conference on Practice and Theory in Public Key Cryp- ' tography(PKC2010)washeldMay26-28,2010,attheEcoleNormaleSup' erieure (ENS) in Paris, France. PKC 2010 was sponsored by the International Associ- ' ation for Cryptologic Research (IACR), in cooperation with the Ecole Normale Sup' erieure (ENS) and the Institut National de Recherche en Informatique et en Automatique (INRIA). The General Chairs of the conference were Michel Abdalla and Pierre-Alain Fouque. The conference received a record number of 145 submissions and each s- missionwas assignedto at least 3 committee members. Submissions co-authored by members of the Program Committee were assigned to at least ?ve comm- tee members. Due to the large number of high-quality submissions, the review process was challenging and we are deeply grateful to the 34 committee m- bers and the 163 external reviewers for their outstanding work. After extensive discussions, the Program Committee selected 29 submissions for presentation during the conference and these are the articles that are included in this v- ume. The best paper was awardedto Petros Mol and Scott Yilek for their paper "Chosen-Ciphertext Security from Slightly Lossy Trapdoor Functions. " The - view process was run using the iChair software, written by Thomas Baign' eres and Matthieu Finiasz from EPFL, LASEC, Switzerland, and we are indebted to them for letting us use their software. The program also included two invited talks: it was a great honor to have Daniele Micciancio and Jacques Stern as invited speakers.

ACNS2009, the7thInternationalConferenceonAppliedCryptographyandN- work Security, was held in Paris-Rocquencourt, France, June 2-5, 2009. ACNS 2009 was organized by the Ecole Normale Sup erieure (ENS), the French - tional Center for Scienti?c Research (CNRS), and the French National Institute for Researchin Computer Science andControl(INRIA), in cooperationwith the InternationalAssociation for CryptologicResearch(IACR). The General Chairs of the conference were Pierre-Alain Fouque and Damien Vergnaud. Theconferencereceived150submissionsandeachsubmissionwasassignedto at least three committee members. Submissions co-authored by members of the Program Committee were assigned to at least four committee members. Due to thelargenumber ofhigh-qualitysubmissions, thereviewprocesswaschallenging andwearedeeplygratefulto the committeemembersandthe externalreviewers for their outstanding work. After meticulous deliberation, the Program C- mittee, which was chaired by Michel Abdalla and David Pointcheval, selected 32 submissions for presentation in the academic track and these are the articles that are included in this volume. Additionally, a few other submissions were selected for presentation in the non-archival industrial track. The best student paper was awarded to Ayman Jarrous for his paper "Secure Hamming Distance Based Computation and Its Applications," co-authoredwith Benny Pinkas. The review process was run using the iChair software, written by Thomas Baigneres and Matthieu Finiasz from EPFL, LASEC, Switzerland and we are indebted to them for letting us use their software. The programalso included four invited talks in addition to the academicand industrial tracks."

This book constitutes the refereed proceedings of the 5th International Conference on Cryptology and Network Security, CANS 2006, held in Suzhou, China in December 2006.

The 26 revised full papers presented together with 2 invited papers were carefully reviewed and selected from 148 submissions. The papers are organized in topical sections on encryption, key exchange, authentication and signatures, proxy signatures, cryptanalysis, implementation, steganalysis and watermarking, boolean functions and stream ciphers, intrusion detection, as well as disponibility and reliability.

This book constitutes the refereed proceedings of the Cryptographers' Track at the RSA Conference 2006, CT-RSA 2006, held in San Jose, CA, USA in February 2006. The book presents 24 papers organized in topical sections on attacks on AES, identification, algebra, integrity, public key encryption, signatures, side-channel attacks, CCA encryption, message authentication, block ciphers, and multi-party computation.

This book constitutes the thoroughly refereed proceedings of the 8th International Conference on the Theory and Application of Cryptographic Techniques in Africa, AFRICACRYPT 2016, held in Fes, Morooco, in April 2016. The 18 papers presented in this book were carefully reviewed and selected from 65 submissions. The aim of Africacrypt 2016 is to provide an international forum for practitioners and researchers from industry, academia and government from all over the world for a wide ranging discussion of all forms of cryptography. Topics of interest are such as lattices; elliptic curves; secret-key cryptanalysis; efficient implementations; secure protocols; and public-key cryptography.

This book constitutes the refereed proceedings of the 7th International Conference on the Theory and Application of Cryptographic Techniques in Africa, AFRICA CRYPT 2014, held in Marrakesh, Morocco in May 2014. The 26 papers presented together with 1 invited talk were carefully reviewed and selected from 83 submissions. The aim of Africa crypt 2014 is to provide an international forum for practitioners and researchers from industry, academia and government from all over the world for a wide ranging discussion of all forms of cryptography and its applications as follows: Public-Key Cryptography, Hash Functions, Secret-Key Cryptanalysis, Number Theory, Hardware Implementation, Protocols and Lattice-based Cryptography.