Praveensankar Manimaran

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Praveensankar Manimaran is a PhD Research Fellow at the University of Oslo, Norway working on Verifiable Credentials and Zero-Knowledge Proofs. His research interests are Blockchain Protocols, Verifiable Credentials, Privacy-Preserving Protocols, Zero-Knowledge Proofs, and Applied Cryptography. As part of the PhD, Praveen designed research projects, identified challenging research problems including privacy issues in VCs revocation, developed novel solutions, and built prototypes to showcase the feasibility. Praveen's PhD gave him experience in identifying and solving non-trivial research problems that directly impact the industry use cases. In addition, Praveen has experience in project management, effective communication and coordination of tasks among team members, and time management.

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email : praveema@ifi.uio.no

Education Details

PhD - Verifiable Credentials and Blockchain

University of Oslo, Norway. (October 2020 - Present)

  • Research in Verifiable Credentials and Blockchain Technologies
  • Worked on privacy issues in VCs's revocation and verification, and developed solutions using techniques such as Zero-Knowledge Proofs, Merkle Tree Accumulators, and BBS Signatures.
  • Implemented prototypes to showcase the practicality of the solutions.
  • Published research papers in top venues: Computer Science Review, and IEEE Blockchain.
  • Installed and maintained Norway's EBSI pilot node
  • Supervisors: Roman Vitenberg (Homepage), Leander Jehl (Homepage)
  • Advisors: Thiago Garrett (Homepage), Mayank Raikwar (Homepage), Arlindo F. Conceição (Homepage)
M.Tech. - Computer Science and Engineering

National Institute of Technology Puducherry, karaikal, India. (July 2018 - June 2020)

  • CGPA - 9.82 / 10 (gold medal)
B.E. - Computer Science and Engineering

PSG College of Technology, Coimbatore, India. (July 2012 - May 2016)

  • CGPA - 7.69 / 10

Research Adoption

EBIP: Secure Privacy-Preserving Revocation of Verifiable Credentials
  • Presents a security vulnerability in EBSI's Dynamic Status List, a revocation protocol for verifiable credentials that addresses the privacy issue of holder's traceability.
  • Adopts a ZKP-based revocation protocol that I developed along with my colleagues during my PhD.
https://hub.ebsi.eu/ebips

Publications

Decentralization Trends in Identity Management: From Federated to Self-Sovereign Identity Management Systems.

Computer Science Review (Volume 58, November 2025, 100776)

  • Studies Federated and Self-Sovereign Identity systems from a conceptual point-of-view.
  • Proposes a generic framework for Identity systems and analyses the architectures and workings of (a) IOTA Id, (b) Indy, and (c) eIDAS v1.0
  • Highlights differences in decentralization and privacy strategies across these systems.
https://www.sciencedirect.com/science/article/pii/S1574013725000528
Prevoke: Privacy-Preserving Configurable Method for Revoking Verifiable Credentials

2024 IEEE International Conference on Blockchain (Blockchain)

  • Prevoke presents key privacy challenges in the revocation protocol and proposes a novel solution.
  • Prevoke keeps track of the revocation status of VCs using a Bloom Filter, and a Merkle Tree Accumulator. These data structures are stored in a DLT using a Smart Contract and updated during revocation of VCs.
  • Prevoke proposes a novel two-phase verification technique which enables efficient and fast verification of almost all valid VCs. Only revoked VCs and handful of valid VCs go through expensive verification
doi: 10.1109/Blockchain62396.2024.00053
Addressing traceability of revocation status of Verifiable Credentials

Work in Progress

  • Formalizes the privacy of holder's traceability in the verifiable credentials system.
  • Proposes a revocation protocol that uses a custom-built Zero-Knowledge Proof circuit.
  • Our proposed protocol outperforms the existing protocols in terms of required bandwidth for issuers and holders.
Link: To appear soon

Projects

Untrace - Implementation

University of Oslo, Norway. (August 2024 - present)

  • This Implementation demonstrates the working of Untrace in a sand-boxed environment.
  • Untrace is the implementation of the protocol that we developed to address the problem of holder's traceability in Verifiable Credentials system
  • We built a custom ZKP-circuit based on groth16 ZKP scheme using the gnark library.
  • This implementation consists of a) standard entities (Issuer, Holder, and Verifier), b) a Smart Contract, c) a mock VC data model based on W3C Specifications.
  • Workflows: 1) issuance, 2) revocation, 3) VP construction and sharing, and 4) VP verification
  • Benchmarks: benchmarked the performed of Untrace and IRMA's revocation technique
  • Results: Untrace outperforms IRMA's protocol in terms of the required bandwidth for holders and issuers
  • Languages: Golang, Solidity, and Python
The GitHub repository will be shared upon request, as the research paper is not yet published.
Prevoke - Implementation

University of Oslo, Norway. (August 2023 - August 2024)

  • This Implementation demonstrates the working of Prevoke in a sand-boxed environment.
  • This implementation consists of a) standard entities (Issuer, Holder, and Verifier), b) a Smart Contract, and c) a mock VC data model based on W3C Specifications.
  • Workflows: 1) issuance, 2) revocation, 3) VP construction and sharing, and 4) VP verification
  • In addition, Smart Contract is deployed on a Private Blockchain using Ganache, hosted in NREC.
  • The entities are hosted as servers and geographically distributed using NREC.
  • Results: We analyzed the performance, latency, and cost of Prevoke for different workloads.
  • Languages: Golang, Solidity, and Python
github link

Work Experience

Summer Research Intern

National Institute of Technology Calicut, Kozhikode, India. (May 2019 - July 2019)

  • Studied about Software Defined Networking, mininet simulator, Named Data Networking and usage of NDN in VANET
  • Designed and developed Intrusion Detection System for NDN Based VANET
Software Engineer

Accolite Software India Pvt. Ltd., Bangalore, India. (July 2016 - March 2017)

  • Worked on the web development
  • Language - C#, Javascript, Web framework - ASP.NET MVC, backend technology - ASP.NET, frontend technology - Jquery and AngularJS, database - Microsoft SQL Server
  • Worked on web development for British Telecommunications through Accolite
Software Engineer Intern

Accolite Software India Pvt. Ltd., Bangalore, India. (January 2016 - April 2016)

  • Worked on the web development
  • Language - C#, Javascript, Web framework - ASP.NET MVC, backend technology - ASP.NET, frontend technology - Jquery and AngularJS, database - Microsoft SQL Server
  • Learned about web development in general and studied ASP.NET and Basic javascript for developing websites
  • Studied about 3 Layer architecture in ASP.NET

Other Activities

Skills
  • Programming Languages: ​ Golang, Solidity,
  • Expertise: ​Verifiable Credentials, Blockchain, Self-Sovereign Identity, Web3
Achievements
  • Scored 96.03 Percentile in Computer Science, GATE 2018
  • Scored 98.02% in HSC exam, 2012
  • Scored Centum in Computer Science, HSC exam, 2012
  • Scored 97.80% in SSLC exam, 2010
  • Scored Centum in Maths and Science, SSLC exam, 2010
Teaching work
Teaching Assistant - IN5420/IN9420: Distributed Blockchain Technologies

University of Oslo, Norway. (Spring 2022, Spring 2023)

Teaching Assistant - IN5020/IN9020: Distributed Systems

University of Oslo, Norway. (Autumn 2022, Aumtum 2023)

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.