https://tokyocryptoday.github.io/ Recent content on Tokyo Crypto Day Hugo -- gohugo.io en-us Ryo Nishimaki Fri, 10 Mar 2023 00:00:00 +0000 https://tokyocryptoday.github.io/links/ Fri, 12 Oct 2018 00:00:00 +0000 https://tokyocryptoday.github.io/links/ nycryptoday Charles River Crypto Day DC AREA CRYPTO DAY Bay Area Crypto Day GTACS Paris Crypto Day London Crypto Day Swiss Crypto Day https://tokyocryptoday.github.io/previous-editions/230330/ Fri, 10 Mar 2023 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/230330/ Place: The conference room 1 (30th) and 4 (31st) in Musashino R&D center, 3-9-11 Midochi-cho, Musashino-shi, Tokyo 180-8585 Registration: No registration is required. Please follow instructions at the reception desk to enter the conference room. Program March 30th (Conference room 1) 13:00 - 14:30: Price of Active Security (Carmit Hazay) 14:45 - 16:15: Zero-knowledge from MPC-in-the-dead: Theory edition (Muthuramakrishnan Venkitasubramaniam) 16:30 - 17:30: Fast Practical Lattice Reduction through Iterated Compression (Keegan Ryan) March 31th (Conference room 4) 13:00 - 14:30: SCALES - MPC with Small Clients and Larger Ephemeral Servers (Carmit Hazay) 14:45 - 16:15: Zero-knowledge from MPC-in-the-head: Practice edition (Muthuramakrishnan Venkitasubramaniam) 16:30 - 17:30: A Key-Recovery Attack against Mitaka in the t-Probing Model (Thomas Prest) Abstracts Price of Active Security Carmit Hazay https://tokyocryptoday.github.io/previous-editions/200309/ Mon, 09 Mar 2020 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/200309/ The next Tokyo Crypto Day will be held on March 9th (Mon) at the University of Tokyo. Canceled Due to the COVID19 issue, this event was canceled. Place: room #63 in Bldg. #6, Faculty of Engineering, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 Program 10:30 - 11:30 Unbounded Dynamic Predicate Compositions in ABE from Standard Assumptions (Junichi Tomida) 13:00 - 14:00 New Approaches for CCA-Secure Encryption (Venkata Koppula) 14:15 - 15:15 Cryptography from Information Loss (Prashant Nalini Vasudevan) 15:30 - 16:30 Uprooting the FALCON tree? https://tokyocryptoday.github.io/previous-editions/191216/ Mon, 16 Dec 2019 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/191216/ http://www.ntt.co.jp/sc/event_e/event20191216.html Program 10:30 - 11:30 Indistinguishability Obfuscation Without Multilinear Maps: New Paradigms via Low Degree Weak Pseudorandomness and Security Amplification (Aayush Jain) 13:00 - 14:00 Black-Box Language Extension of Non-Interactive Zero-Knowledge Arguments (Miguel Ambrona) 14:15 - 15:15 Structure-Preserving and Re-randomizable RCCA-secure Public Key Encryption and its Applications (Antonio Faonio) 15:30 - 16:30 On the (In)security of Kilian-Based SNARGs (Fermi Ma) Abstracts Indistinguishability Obfuscation Without Multilinear Maps: New Paradigms via Low Degree Weak Pseudorandomness and Security Amplification Aayush Jain (UCLA) https://tokyocryptoday.github.io/previous-editions/190705/ Fri, 05 Jul 2019 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/190705/ http://www.ntt.co.jp/sc/event_e/event20190705.html Program 10:30 - 11:30 CCA Security and Trapdoor Functions via Key-Dependent-Message Security (Takahiro Matsuda) 12:45 - 13:45 Multi-Client Functional Encryption for Inner Products (Romain Gay) 14:00 - 15:00 Attribute Based Encryption (and more) for Nondeterministic Finite Automata from LWE (Shota Yamada) 15:10 - 16:10 Unbounded Dynamic Predicate Compositions in Attribute-based Encryption (Nuttapong Attrapadung) Abstracts CCA Security and Trapdoor Functions via Key-Dependent-Message Security Takahiro Matsuda (AIST) We study the relationship among public-key encryption (PKE) satisfying indistinguishability against chosen plaintext attacks (IND-CPA security), that against chosen ciphertext attacks (IND-CCA security), and trapdoor functions (TDF). https://tokyocryptoday.github.io/previous-editions/190308/ Fri, 08 Mar 2019 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/190308/ http://www.ntt.co.jp/sc/event_e/event20190308.html Program Collusion Resistant Traitor Tracing from Learning with Errors (Rishab Goyal) Fine-grained quantum computational supremacy (Tomoyuki Morimae) Non-Malleable Codes for Decision Trees (and more) (Marshall Ball) Finding Collisions in a Quantum World: Quantum Black-Box Separation of Collision-Resistance and One-Wayness (Akinori Hosoyamada) Abstracts Collusion Resistant Traitor Tracing from Learning with Errors Rishab Goyal (UT Austin) In this work we provide a traitor tracing scheme with ciphertexts that grow polynomially in log(N) where N is the number of users and prove it secure under the Learning with Errors (LWE) assumption. https://tokyocryptoday.github.io/previous-editions/181026/ Fri, 26 Oct 2018 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/181026/ http://www.ntt.co.jp/sc/event_e/event20181026.html Program New Techniques for obtaining Adaptive Security in Garbling Schemes (Akshayaram Srinivasan) Secret Sharing and CDS (Tianren Liu) New Bleichenbacher Records: Fault Attacks on qDSA Signatures (Akira Takahashi) Abstracts New Techniques for obtaining Adaptive Security in Garbling Schemes Akshayaram Srinivasan (UC Berkeley) Garbled circuits are fundamental cryptographic primitives. They have diverse applications such as designing secure multiparty computation protocols, in parallel cryptography, in constructing program obfuscation and more recently in constructing IBE schemes without pairings. https://tokyocryptoday.github.io/previous-editions/180525/ Fri, 25 May 2018 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/180525/ Program Forgery and Impersonation Attacks against of LINE’s End-to-End Encryption Schemes (Kazuhiko Minematsu) Count-then-Permute: a Precision-free Alternative to Inversion Sampling (Kentarou Sasaki) Improved (Almost) Tightly-Secure Structure-Preserving Signatures (Miyako Ohkubo) Abstracts Forgery and Impersonation Attacks against of LINE’s End-to-End Encryption Schemes Kazuhiko Minematsu (NEC) LINE is a mobile messaging application quite popular in Japan and several other east Asian countries. In this talk, we study the security of LINE’s End-to-End Encryption (E2EE) schemes, called Letter Sealing, by investigating the specifications described in the whitepaper published by the developer (the LINE corporation). https://tokyocryptoday.github.io/previous-editions/180302/ Fri, 02 Mar 2018 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/180302/ Program Encoding Predicates by Arithmetic Circuits and Its Applications (Shuich Katsumata) Threshold Cryptosystems From Threshold Fully Homomorphic Encryption (Sam Kim) Notes On GGH13 Without The Presence Of Ideals (Alex Davidson) Constrained PRF for NC1 in Traditional Groups (Takashi Yamakawa) Abstracts Encoding Predicates by Arithmetic Circuits and Its Applications Shuich Katsumata (The University of Tokyo) Predicates are used in cryptography as a fundamental tool to control the disclosure of secrets. However, how to embed a particular predicate into a cryptographic primitive is usually not given much attention. https://tokyocryptoday.github.io/previous-editions/171020/ Fri, 20 Oct 2017 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/171020/ Program A Unified Approach to Constructing Black-box UC Protocols in Trusted Setup Models (Susumu Kiyoshima) Asymptotically Compact Adaptively Secure Lattice IBEs and Verifiable Random Functions via Generalized Partitioning Techniques (Shota Yamada) Side-Channel Attacks on BLISS Lattice-Based Signatures (Mehdi Tibouchi) Secure AES computation comparable to local AES computation (Ryo Kikuchi) Abstracts A Unified Approach to Constructing Black-box UC Protocols in Trusted Setup Models Susumu Kiyoshima (NTT Secure Platform Laboratories) We present a unified framework for obtaining black-box constructions of Universal Composable (UC) protocol in trusted setup models. https://tokyocryptoday.github.io/previous-editions/170602/ Fri, 02 Jun 2017 00:00:00 +0000 https://tokyocryptoday.github.io/previous-editions/170602/ Program From Single-Key to Collusion-Resistant Secret-Key Functional Encryption by Leveraging Succinctness (Fuyuki Kitagawa) Small CRT-Exponent RSA Revisited (Atsushi Takayasu) Privacy-Preserving Aggregation of Time-Series Data with Public Verifiability from Simple Assumptions (Keita Emura) Abstracts From Single-Key to Collusion-Resistant Secret-Key Functional Encryption by Leveraging Succinctness Fuyuki Kitagawa (Tokyo Tech) We show how to construct a secret-key functional encryption (SKFE) scheme that supports unbounded polynomially many functional decryption keys solely from an SKFE scheme that supports only one functional decryption key. https://tokyocryptoday.github.io/upcoming/ Mon, 01 Jan 0001 00:00:00 +0000 https://tokyocryptoday.github.io/upcoming/ The next Tokyo Crypto Day will be held on December 8th (Fri) at the Musashino R&D center. Place: The conference room in Musashino R&D center, 3-9-11 Midochi-cho, Musashino-shi, Tokyo 180-8585 Registration: No registration is required. Please follow instructions at the reception desk to enter the conference room. - Speakers - Andrej Bogdanov Siyao Guo Alon Rosen Yasunari Suzuki Takashi Yamakawa (not confirmed yet) - Program - 9:15 - 10:15 Andrej Bogdanov Classical simulation of one-query quantum distinguishers 10:30 - 11:30 Siyao Guo Time-space tradeoffs for Function Inversion 13:00 - 14:00 Alon Rosen Public-Key Encryption, Local Pseudorandom Generators, and the Low-Degree Method 14:15 - 15:15 Takashi Yamakawa Classical vs Quantum Advice and Proofs under Classically-Accessible Oracle 15:30 - 16:30 Yasunari Suzuki Design and Resource Estimation of Realistic Fault-Tolerant Quantum Computing - Abstracts - - Classical simulation of one-query quantum distinguishers Andrej Bogdanov https://tokyocryptoday.github.io/about/ Mon, 01 Jan 0001 00:00:00 +0000 https://tokyocryptoday.github.io/about/ Tokyo Crypto Day is a half-day (or full-day) of cryptography talks in the Tokyo area. This event is organized by Ryo Nishimaki.