The NTNU Applied Cryptology Lab (NaCl) is a research group at the Department of Information Security and Communication Technology and the Department of Mathematical Sciences at NTNU, with members in Trondheim and Gjøvik. We design, analyze, and implement cryptographic protocols and systems that protect the security and privacy of digital communication and computation. NTNU has taught and researched cryptography since the 1980s, and more than 35 PhD candidates have completed a doctorate in cryptography in the group.

Our research spans the theory and practice of cryptography, with a particular focus on security against quantum adversaries. Current topics include lattice-based cryptography, threshold and blind signatures, zero-knowledge proofs, homomorphic encryption, key exchange, isogeny-based and symmetric cryptography, electronic voting, digital identity wallets, data privacy, and cryptographic engineering. Our members publish at the leading venues in the field, such as IACR Crypto, Eurocrypt, and Asiacrypt, ACM CCS, IEEE S&P, and USENIX Security.

We collaborate with research groups in Norway and abroad, and with industry and the public sector, through projects funded by the Research Council of Norway, Horizon Europe, and NTNU. We organized IACR Eurocrypt 2022 in Trondheim and IACR Public-Key Cryptography 2025 in Røros, and our members regularly serve on the program committees of the top cryptography conferences.