Cryptographers from the NTT Research Cryptography & Information Security (CIS) Lab, NTT Social Informatics Laboratories (SIL) and NTT Corporation (NTT) participated in recent conferences hosted by the International Association for Cryptographic Research (IACR) and the Association for Computing Machinery (ACM). Scientists from these groups delivered ten papers at the IACR Theory of Cryptography Conference (TCC) 2023 and another eight papers at the ACM Conference on Computer and Communications Security (CCS) 2023. One of the CCS papers, co-authored by CIS Lab Scientist Ilan Komargodski, won a Distinguished Paper Award.
The IACR’s TCC event solicits papers representing original research on foundational and theoretical aspects of cryptography. The TCC conference focuses on “the paradigms, approaches and techniques used to conceptualize natural cryptographic problems and provide algorithmic solutions to them.” At this year’s event, held Nov. 29–Dec. 2, 2023, in Taipei, the program included six CIS Lab papers, three SIL papers, and one joint CIS Lab/SIL paper. These ten papers, out of the 68 that were accepted for presentation at TCC, fell under these session headings: Anonymity, Surveillance and Tampering; Encryption; IOPs (Interactive Oracle Proofs) and Succinctness; Multi-Party Computation; Proof Systems; and Quantum Crypto.
Reflecting their standing in theoretical cryptography, several members of the CIS Lab have held leadership roles at TCC recently. CIS Lab Senior Scientist Hoeteck Wee served as one of two program chairs for TCC 2023. (The event also includes two general co-chairs.) CIS Lab Director and Distinguished Scientist Brent Waters was a program chair in 2021. CIS Lab Senior Scientist Elette Boyle has also been named program co-chair for TCC 2024.
At CCS 2023, held Nov. 26–30 in Copenhagen, CIS Lab and NTT cryptographers delivered six and two papers, respectively. These papers fell under these session headings: Advanced Public Key Encryption; Digital Signatures; Language Models & Verification; Multiparty Computation; Oblivious Algorithms and Data Structures; and Security of Cryptographic Protocols and Implementation. More focused on applied cryptography than the TCC event, CSS is the annual flagship conference of the ACM’s Special Interest Group on Security, Audit and Control (SIGSAC). It accepted 234 papers this year. The award-winning paper co-authored by Dr. Komargodski was titled “FutORAMa: A Concretely Efficient Hierarchical Oblivious RAM.”
The context for the “FutORAMa” paper is cloud computing. Oblivious random access machine (ORAM) is an algorithmic tool that “scrambles” the observed patterns of accessing data remotely stored in the cloud. Those access patterns can reveal information that compromises the privacy of data, even when encrypted. This paper presents a new and efficient construction of hierarchical ORAM, one of the main approaches for designing ORAMs. “Prior to our work,” the co-authors write, “the belief was that hierarchical ORAM-based constructions were inherently too expensive in practice.” For more on Dr. Komargodski and his research agenda, please see this short video and this profile and Q&A.
