Tapas Pal

Room 230, CS 50.34

Am Fasanengarten 5

76131 Karlsruhe, Germany

I am a researcher of the KASTEL Security Research Labs (Secure Computation & Communication group) within the Research Group Rupp, headed by Andy Rupp, under KASTEL: Cryptography and Security Group, at the Karlsruhe Institute of Technology.

Previously, I was a postdoc at the Social Informatics Laboratories of NTT Japan, hosted by Ryo Nishimaki. I obtained my PhD from the Department of Mathematics, IIT Kharagpur, under the supervision of Prof. Ratna Dutta. I have also been a research intern at the CIS Laboratories of NTT Research, working with Pratish Datta on computing over encrypted data, and a visiting scientist at the R. C. Bose Centre for Cryptology and Security, ISI Kolkata, hosted by Prof. Mridul Nandi.

My research designs provably-secure cryptographic primitives for computing on encrypted data — spanning functional encryption (attribute-based, registered, and multi-authority variants), anamorphic cryptography, verifiable computation, and privacy-enhancing technologies — with an eye toward decentralized trust and privacy-preserving digital infrastructure.

news

May 29, 2026	I am invited to join the PC of SPACE’26.
May 04, 2026	A paper on anamorphic cryptography is accepted to Crypto 2026!
Feb 13, 2026	A paper on registered FE for attribute-weighted sums is accepted by PKC 2026.
Feb 12, 2026	I am invited to join the PC of PKC 2027.
Nov 06, 2025	I am invited to join the PC of ACM APKC 2026.
Sep 10, 2025	I am invited to join the PC of ACM WWW’26.
Aug 28, 2025	A paper on registered (pseudorandom) functional encryption for TMs is now available to ePrint.
Aug 10, 2025	A paper on a generic framework for registered FEs is accepted by Asiacrypt’25.
Jul 09, 2025	I am invited to join the PC of ACM CCS 2026 for the Privacy and Anonymity Track.
Apr 04, 2025	I am invited to join the PC of Indocrypt’25.
Mar 11, 2025	Our traceable functional encryption paper is accepted for publication at the IACR CiC journal.
Feb 05, 2025	A paper on multi-client attribute-based unbounded IPFE is accepted to PKC’25!
Nov 05, 2024	I am invited to join the reviewer panel of the Mathematical Reviews of the American Mathematical Society (AMS).
Aug 25, 2024	Our paper on registration-based linear functional encryption with access control is accepted to Asiacrypt’24!
Jul 27, 2024	The full version of our Asiscrypt’22 paper is published at Designs, Codes and Cryptography!
May 12, 2024	A paper on adaptively secure inner product encryption is accepted for publication at the journal of Theoretical Computer Science.
May 02, 2024	A paper on certified everlasting secure FE is accepted by Eurocrypt 2024!
Apr 05, 2024	A paper on functional encryption with unbounded data (SACfe) is accepted by IEEE EurpSP’24!
Sep 01, 2023	Research visit to the University of St. Gallen and a talk at Swiss Crypto Day
Jun 13, 2023	A paper on unbounded predicate inner product FE is accepted for publication at the Journal of Cryptology!
May 25, 2023	The full version of our Asiscrypt’21 paper is published at Designs, Codes and Cryptography!
Jan 25, 2023	A paper on multi-authority attribute-based inner-product FE is accepted by PKC 2023.
Jun 24, 2019	Research visit to the University of Auckland

latest posts

Jun 10, 2026	The Art of Covert Communications
Dec 19, 2025	Computing on Encrypted Data Without a Central Authority
Apr 15, 2024	Registration Model for Functional Encryption: Linear Functions with Access Control

selected publications

CRYPTO

Simple Public Key Anamorphic Encryption and Signature using Multi-Message Extensions

Shalini Banerjee, Tapas Pal, Andy Rupp, and Daniel Slamanig

In Annual International Cryptology Conference (CRYPTO), 2026

Bib HTML

@inproceedings{banerjee2026anamorphic,
  title = {Simple Public Key Anamorphic Encryption and Signature using Multi-Message Extensions},
  author = {Banerjee, Shalini and Pal, Tapas and Rupp, Andy and Slamanig, Daniel},
  booktitle = {Annual International Cryptology Conference (CRYPTO)},
  year = {2026},
}

ASIACRYPT

A General Framework for Registered Functional Encryption via User-Specific Pre-Constraining

Tapas Pal and Robert Schädlich

In International Conference on the Theory and Application of Cryptology and Information Security (ASIACRYPT), 2025

Bib HTML

@inproceedings{pal2025framework,
  title = {A General Framework for Registered Functional Encryption via User-Specific Pre-Constraining},
  author = {Pal, Tapas and Sch{\"a}dlich, Robert},
  booktitle = {International Conference on the Theory and Application of Cryptology and Information Security (ASIACRYPT)},
  year = {2025},
}

ASIACRYPT

Registered FE beyond Predicates: (Attribute-Based) Linear Functions and more

Pratish Datta, Tapas Pal, and Shota Yamada

In International Conference on the Theory and Application of Cryptology and Information Security (ASIACRYPT), 2024

Bib HTML

@inproceedings{datta2024registered,
  title = {Registered FE beyond Predicates: (Attribute-Based) Linear Functions and more},
  author = {Datta, Pratish and Pal, Tapas and Yamada, Shota},
  booktitle = {International Conference on the Theory and Application of Cryptology and Information Security (ASIACRYPT)},
  year = {2024},
}

EUROCRYPT

Certified Everlasting Secure Collusion-Resistant Functional Encryption, and More

Taiga Hiroka, Fuyuki Kitagawa, Tomoyuki Morimae, Ryo Nishimaki, Tapas Pal, and 1 more author

In Annual International Conference on the Theory and Applications of Cryptographic Techniques (EUROCRYPT), 2024

Bib HTML

@inproceedings{hiroka2024certified,
  title = {Certified Everlasting Secure Collusion-Resistant Functional Encryption, and More},
  author = {Hiroka, Taiga and Kitagawa, Fuyuki and Morimae, Tomoyuki and Nishimaki, Ryo and Pal, Tapas and Yamakawa, Takashi},
  booktitle = {Annual International Conference on the Theory and Applications of Cryptographic Techniques (EUROCRYPT)},
  year = {2024},
}

JoC

Unbounded Predicate Inner Product Functional Encryption from Pairings

Uddipana Dowerah, Subhranil Dutta, Aikaterini Mitrokotsa, Sayantan Mukherjee, and Tapas Pal

Journal of Cryptology (JoC), 2023

Bib HTML

@article{dowerah2023unbounded,
  title = {Unbounded Predicate Inner Product Functional Encryption from Pairings},
  author = {Dowerah, Uddipana and Dutta, Subhranil and Mitrokotsa, Aikaterini and Mukherjee, Sayantan and Pal, Tapas},
  journal = {Journal of Cryptology (JoC)},
  year = {2023},
}