Sujoy Sinha Roy

I am a Lecturer (Assistant Professor) in Cyber Security in the University of Birmingham's School of Computer Science, and a member of the Security and Privacy research group. The National Cyber Security Centre (NCSC) and the Engineering and Physical Sciences Research Council (EPSRC) jointly recognise our research group as an Academic Centre of Excellence in Cyber Security Research (ACE-CSR).

PhD Openings

  • NCSC funded PhD position in "Hardware acceleration of isogeny-based cryptography" [Application closed].
  • University of Birmingham funded PhD position in "Investigating implementation aspects of lattice-based cryptography on hardware and software platforms" [Application closed].

    Master/Bachelor project topics:

    1. Design and analysis of post-quantum public-key cryptographic schemes

    2. their efficient implementations

    3. their side-channel security

    4. Homomorphic encryption

    5. Security of Software-defined networking (SDN)

    Current students

    Matthew Walters (MSci)

    Updates

  • Our paper Generic Side-channel attacks on CCA-secure lattice-based PKE and KEM schemes

  • News article published in NewStatesman How to prevent a crypto-apocalypse

  • Our post-quantum public-key encapsulation scheme 'Saber' has moved to the Round 2 of NIST's Post-Quantum Standardization Project. More information on Saber.
  • Our paper on computer architecture design for homomorphic computing on encrypted data has been accepted in High Performance Computing Architecture (HPCA 2019). It is a top conference in Computing Systems with acceptance rate 19%.
  • FWO has awarded my PhD thesis “Public Key Cryptography on Hardware Platforms: Design and Analysis of Elliptic Curve and Lattice-based Cryptoprocessors“ the IBM Innovation Award 2018. The Award is a scientific prize that acknowledges an outstanding doctoral thesis in informatics.
  • Our paper "Constant-time discrete Gaussian sampling" has been selected as featured article in IEEE Transactions on Computers, November 2018. More info here. Video
  • My article "Public Key Cryptography on Hardware Platforms: Design and Analysis of Lattice-based Cryptoprocessors" is now available in GeniaaL, issue 42.
  • Blog on constant-time Gaussian sampling for lattice-based cryptography is now available.
  • Our paper "Saber on ARM: CCA-secure module lattice-based key encapsulation on ARM" has been published in TCHES 2018. Author’s version of the paper is available in Eprint 2018/682 and the source codes are available in Github
  • Research

    Research Interests: I am interested in developing efficient algorithms, design methodologies and hardware/software architectures for computation-intensive tasks targeting new-generation heterogeneous computing platforms. I have contributed to the progress of hardware security by designing and engineering cryptosystems, analyzing their physical security properties and implementing countermeasures against side-channel and fault attacks. I am one of the developers of SABER KEM which is a candidate in NIST's 2nd round Post-Quantum Cryptography Standardization project.

    My research experience spans two broad areas: Public-key Cryptography and Privacy-preserving Cloud Computing using Homomorphic Encryption, with focus on implementation aspects.

    Program Committee

    • In the program committees of SAC 2018, SPACE 2018, VLSID 2018, CHES 2019, Indocrypt 2019, SPACE 2019, VLSID 2019.
    • Reviewer of IEEE Transactions on VLSI, IEEE Transactions on Circuits and Systems, IEEE Transactions on Computers, Journal of Cryptographic Engineering.

    Projects

    • Implementation of lattice-based PKC. The main focus of my doctoral research was the feasibility-study of lattice-based post-quantum cryptographic schemes. When I started my doctoral research, almost all of the published literature covered the theoretical aspects of lattice-based cryptography; not much was known about their practical efficiency. We designed efficient building blocks for lattice-based cryptography and to show that lattice-based public-key is practical. We designed a compact coprocessor architecture in hardware that can compute post-quantum encryption/decryption in 20/9 micro seconds. Further, we analyzed side channel security of the implemented schemes and proposed countermeasures. Recently we have constructed and implemented a lattice-based key encapsulation scheme called 'Saber' based on a new lattice-problem called module learning with rounding. The scheme and its implementation have been submitted in the NIST's post-quantum standardization process. See our web page https://www.esat.kuleuven.be/cosic/pqcrypto/saber/ on Saber for more details.

    • Implementation of lattice-based homomorphic encryption. During my doctoral research, we also designed fast and parallel algorithms and hardware accelerators for lattice-based homomorphic encryption schemes using FPGAs. We observed that though the computation intensive arithmetic can be accelerated, the overhead of external memory access becomes a bottleneck. Then we proposed a more practical scheme that interpolates between homomorphic encryption and multi-party computation and achieves faster evaluation time. Recently, we have designed a programmable processor architecture for homomorphically evaluating neural networks in the context of smart meters.

    • Implementation of elliptic curve-based PKC. We successfully developed a theoretical model to estimate optimal design configurations for implementing an elliptic curve cryptoprocessor. The research project resulted in a very fast processor architecture for elliptic curve cryptography. We also designed a high-security elliptic curve PKC processor for resource-constrained IoT platforms. Previous proposals focused predominantly on low-security elliptic-curves. We were the first to design lightweight algorithms that are computationally efficient as well as resistant against simple side-channel analysis-based attacks. The lightweight PKC architecture for IoT has received attention from the chip designing industry.

    Biography

    I received the BS degree in electronics and telecommunication engineering from Indian Institute of Engineering Science and Technology, Shibpur, in 2007 and received the MS degree in computer science and engineering from Indian Institute of Technology, Kharagpur, in 2012. In June 2017 I received the PhD degree with `Summa cum laude with congratulations from the examination committee' (~top 5%) from the Computer Security and Industrial Cryptography (COSIC) group, Department of Electrical Engineering (ESAT), KU Leuven, Belgium. I received the IBM Innovation Award 2018 in recognition of an outstanding doctoral thesis in informatics.

     

    Publications

    P. Ravi, S. Sinha Roy, A. Chattopadhyay and S. Bhasin, "Generic Side-channel attacks on CCA-secure lattice-based PKE and KEM schemes." In Cryptology ePrint Archive, Report 2019/948, 2019.
    M. Walters and S. Sinha Roy, "Constant-time BCH Error-Correcting Code." In Cryptology ePrint Archive, Report 2019/155, 2019.
    A. Karmakar, S. Sinha Roy, I. Verbauwhede, and F. Vercauteren, "Pushing the speed limit of constant-time discrete Gaussian sampling. A case study on Falcon.," In 2019th Design Automation Conference (DAC 2019), IEEE, 16 pages, 2019.
    S. Sinha Roy, F. Turan, K. Jarvinen, F. Vercauteren, and I. Verbauwhede, "FPGA-based High-Performance Parallel Architecture for Homomorphic Computing on Encrypted Data," In 25th IEEE International Symposium on High-Performance Computer Architecture, IEEE, 12 pages, 2019.
    J. Balasch, A. Beckers, D. Bozilov, S. Sinha Roy, F. Turan, and I. Verbauwhede, "Teaching HW/SW codesign with a Zynq ARM/FPGA SoC," In European Workshop on Microelectronics Education, IEEE, pp. 63-66, 2018.
    A. Karmakar, J. Bermudo Mera, S. Sinha Roy, and I. Verbauwhede, "Saber on ARM. CCA-secure module lattice-based key encapsulation on ARM," In Transactions in Cryptographic Hardware and Embedded Systems, Lecture Notes in Computer Science, Springer-Verlag, 24 pages, 2018.
    J. P. D'Anvers, A. Karmakar, S. Sinha Roy, and F. Vercauteren, "Saber: Module-LWR based key exchange, CPA-secure encryption and CCA-secure KEM," In Progress in Cryptology - AFRICACRYPT 2018, Lecture Notes in Computer Science, Springer-Verlag, 23 pages, 2018.
    J. P. D'Anvers, A. Karmakar, S. Sinha Roy, and F. Vercauteren, "SABER: Mod-LWR based KEM," In First PQC Standardization Conference, 31 pages, 2018.
    S. Sinha Roy, K. Järvinen, J. Vliegen, F. Vercauteren, and I. Verbauwhede, "HEPCloud: An FPGA-Based Multicore Processor for FV Somewhat Homomorphic Function Evaluation," IEEE Transactions on Computers 67(11), pp. 1637-1650, 2018.
    K. Järvinen, S. Sinha Roy, and I. Verbauwhede, "Arithmetic of tau-adic expansions for lightweight Koblitz curve cryptography," Journal of Cryptographic Engineering 8(4), pp. 285 - 300, 2018.
    A. Karmakar, S. Sinha Roy, O. Reparaz, I. Verbauwhede, and F. Vercauteren, "Constant-time Discrete Gaussian Sampling," IEEE Transactions on Computers SI PQcrypto(accepted), 12 pages, 2017.
    Z. Liu, T. Poppelmann, T. Oder, H. Seo, J. Großschädl, T. Güneysu, H. Kim, S. Sinha Roy, and I. Verbauwhede, "High-Performance Ideal Lattice-Based Cryptography on 8-Bit AVR Microcontrollers," Transactions on Embedded Computing Systems (TECS) - Special Issue on Secure and Fault-Tolerant 16(117), 24 pages, 2017.
    S. Sinha Roy, "Public Key Cryptography on Hardware Platforms: Design and Analysis of Elliptic Curve and Lattice-based Cryptoprocessors," PhD thesis, KU Leuven, I. Verbauwhede, and F. Vercauteren (promotors), 192 pages, 2017.
    S. Sinha Roy, F. Vercauteren, J. Vliegen, and I. Verbauwhede, "Hardware Assisted Fully Homomorphic Function Evaluation and Encrypted Search," IEEE Transactions on Computers PP(99), pp. 1-12, 2017.
    S. Sinha Roy, A. Karmakar, and I. Verbauwhede, "Ring-LWE: Applications to cryptography andtheir efficient realization," In International Conference on Security, Privacy and Applied Cryptography Engineering, Lecture Notes in Computer Science 8204, A. Agarwal, M. Arun Kumar, and S. Chamarty (eds.), Springer-Verlag, 10 pages, 2016.
    A. Karmakar, S. Sinha Roy, I. Verbauwhede, and F. Vercauteren, "Efficient Finite Field Multiplication for Isogeny Based Post Quantum Cryptography," In International Workshop on the Arithmetic of Finite Fields (WAIFI 2016), Lecture Notes in Computer Science, Springer-Verlag, 15 pages, 2016.
    O. Reparaz, S. Sinha Roy, R. De Clercq, I. Verbauwhede, and F. Vercauteren, "Masking ring-LWE," Journal of Cryptographic Engineering 6(2), 17 pages, 2016.
    J. Bosmans, S. Sinha Roy, K. Jarvinen, and I. Verbauwhede, "A Tiny Coprocessor for Elliptic Curve Cryptography over the 256-bit NIST Prime Field.," VLSI Design and 2016 15th International Conference on Embedded Systems (VLSID) -(-), 6 pages, 2016.
    O. Reparaz, S. Sinha Roy, R. De Clercq, F. Vercauteren, and I. Verbauwhede, "Additively Homomorphic ring-LWE Masking," In Post-Quantum Cryptography, Lecture Notes in Computer Science 9606, T. Takagi (ed.), Springer-Verlag, pp. 233-244, 2016.
    D. Mukhopadhyay, S. Sinha Roy, and I. Verbauwhede, "Tutorial: Embedded Security," VLSI Design and 2016 15th International Conference on Embedded Systems (VLSID), Kolkata, IN, 2016.
    O. Reparaz, S. Sinha Roy, I. Verbauwhede, and F. Vercauteren, "A masked ring-LWE implementation," In Cryptographic Hardware and Embedded Systems - CHES 2015, Lecture Notes in Computer Science 9293, T. Güneysu, and H. Handschuh (eds.), Springer-Verlag, pp. 683-702, 2015.
    Z. Liu, H. Seo, S. Sinha Roy, J. Großschädl, H. Kim, and I. Verbauwhede, "Efficient Ring-LWE Encryption on 8-bit AVR Processors," In Cryptographic Hardware and Embedded Systems - CHES 2015, Lecture Notes in Computer Science 9293, T. Güneysu, and H. Handschuh (eds.), Springer-Verlag, 22 pages, 2015.
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