Jiaxin Pan

I am an Associate Professor (førsteamanuensis) at NTNU (Norway).

Before that I was a postdoc at KIT (Germany) in the group of Dennis Hofheinz. In July 2016 I obtained my PhD from Ruhr-University Bochum (Germany) under the supervision of Eike Kiltz. I am interested in theoretical and practical cryptography in general.

Email: first.last at NTNU.no.

Research Interests

  • Cryptosystems that are scalable (tightly secure) and suitable for Big Data applications

  • Foundations for large-scale privacy, such as (non-interactive) zero-knowledge proof systems

  • Efficient quantum-secure lattice-based cryptosystems

Very recently, I am passionate in proposing and improving security proofs for real-world protocols, which bridges the gap between theoretical and practical cryptography.

Professional Activities

Program Committee Member



  • Journals: ACM Transactions on Algorithms; Journal of Cryptology; Designs, Codes, and Cryptography; IET Information Security; Theoretical Computer Science.

Organizing Committee Member


Teaching Activities

  • Elementary Discrete Mathematics (NTNU, Spring 2021)

  • Cryptography (NTNU, Fall 2020)

  • Digital Signatures (Lecture at KIT, Winter semester 2018/2019)

  • Cryptographic Protocols (Tutorial at RUB, Summer semester 2015)

  • Several student seminars at both KIT and RUB

Thesis Supervisions

  • Roman Langrehr (MA): Unbounded HIBE with Better Security

    • (Results led to publications at ASIACRYPT and PKC)

  • Benedikt Wagner (BA): Tightly Secure Blind Signatures

    • (It was awarded the SICK Science Award 2019 for the best bachelor thesis )

  • Julia Kastner (MA): On Knowledge Assumptions and the Algebraic Group Model

  • Roman Langrehr (BA): Identity-based Cryptography from Affine MACs

Student Intern

  • Roman Langrehr from KIT, from 2018 to 2019.

    • (Results led to an invitation to publish in the Journal of Cryptology)


  • Signed Diffie-Hellman Key Exchange with Tight Security

with Chen Qian and Magnus Ringerud (to appear at CT-RSA 2021)

  • Unbounded HIBE with Tight Security

with Roman Langrehr (appeared at ASIACRYPT 2020, full version)

  • Signatures with Tight Multi-User Security from Search Assumptions

with Magnus Ringerud (appeared at ESORICS 2020)

  • Hierarchical Identity-Based Encryption with Tight Multi-Challenge Security

with Roman Langrehr (appeared at PKC 2020, full version)

  • Shorter QA-NIZK and SPS with Tighter Security

with Masayuki Abe, Charanjit Jutla, Miyako Ohkubo, Arnab Roy, and Yuyu Wang (appeared at ASIACRYPT 2019, full version).

  • Tightly Secure Hierarchical Identity-Based Encryption

with Roman Langrehr (appeared at PKC 2019, full version). Invited and accepted to Journal of Cryptology.

  • Identity-Based Encryption Tightly Secure Under Chosen-Ciphertext Attacks

with Dennis Hofheinz and Dingding Jia (appeared at ASIACRYPT 2018, full version).

  • Simple and More Efficient PRFs with Tight Security from LWE and Matrix-DDH

with Tibor Jager and Rafael Kurek (appeared at ASIACRYPT 2018, full version)

  • More Efficient (Almost) Tightly Secure Structure-Preserving Signatures

with Romain Gay, Dennis Hofheinz, and Lisa Kohl (appeared at EUROCRYPT 2018, full version)

  • Tightly-Secure Signatures from Five-Move Identification Protocols

with Eike Kiltz and Julian Loss (appeared at ASIACRYPT 2017, full version)

  • Compact Structure-Preserving Signatures with Almost Tight Security

with Masayuki Abe, Dennis Hofheinz, Ryo Nishimaki, and Miyako Ohkubo (appeared at CRYPTO 2017, full version)

  • Optimal Security Proofs for Signatures from Identification Schemes

with Eike Kiltz and Daniel Masny (appeared at CRYPTO 2016, full version)

  • Unified Security Model of Authenticated Key Exchange with Specific Adversarial Capabilities

with Weiqiang Wen and Libin Wang (appeared at journal of IET Information Security)

  • Structure-Preserving Signatures from Standard Assumptions, Revisited

with Eike Kiltz and Hoeteck Wee (appeared at CRYPTO 2015, full version)

  • Tightly-Secure Signatures from Chameleon Hash Functions

with Olivier Blazy, Saqib A. Kakvi, and Eike Kiltz (appeared at PKC 2015, full version)

  • (Hierarchical) Identity-Based Encryption from Affine Message Authentication

with Olivier Blazy, and Eike Kiltz (appeared at CRYPTO 2014, full version)

You can also check my DBLP for my latest publications.