---
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@article{PhysRev.47.777,
  abbr={PhysRev},
  title={Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?},
  author={<NAME>. and <NAME>. and <NAME>.},
  abstract={In a complete theory there is an element corresponding to each element of reality. A sufficient condition for the reality of a physical quantity is the possibility of predicting it with certainty, without disturbing the system. In quantum mechanics in the case of two physical quantities described by non-commuting operators, the knowledge of one precludes the knowledge of the other. Then either (1) the description of reality given by the wave function in quantum mechanics is not complete or (2) these two quantities cannot have simultaneous reality. Consideration of the problem of making predictions concerning a system on the basis of measurements made on another system that had previously interacted with it leads to the result that if (1) is false then (2) is also false. One is thus led to conclude that the description of reality as given by a wave function is not complete.},
  journal={Phys. Rev.,},
  volume={47},
  issue={10},
  pages={777--780},
  numpages={0},
  year={1935},
  month={May},
  publisher=aps,
  doi={10.1103/PhysRev.47.777},
  url={http://link.aps.org/doi/10.1103/PhysRev.47.777},
  html={https://journals.aps.org/pr/abstract/10.1103/PhysRev.47.777},
  pdf={example_pdf.pdf},
  selected={true},
  manuscript={false}
}

@article{cryptoeprint:2021:1033,
    abbr={ePrint},
    author       = {<NAME> and <NAME>},
    journal={Cryptology ePrint Archive},
    title        = {Limits of Polynomial Packings for $Z_\{p^k\}$ and $F_\{p^k\}$},
    year         = {2021},
    manuscript={true},
    eprint = {2021/1033},
    abstract={We formally define polynomial packing methods and initiate a unified study of related concepts in various contexts of cryptography. This includes homomorphic encryption (HE) packing and reverse multiplication-friendly embedding (RMFE) in information-theoretically secure multi-party computation (MPC). We prove several upper bounds or impossibility results on packing methods for $Z_\{p^k\}$ or $F_\{p^k\}$-messages into $Z_\{p^t\}[x]/f(x)$ regarding (i) packing density, (ii) level-consistency, and (iii) surjectivity. These results have implications on recent development of HE-based MPC over Z2k secure against actively corrupted majority and provide new proofs for upper bounds on RMFE.}
}


@article{cheon2021scaled,
  abbr={JKMS},
  title={On the Scaled Inverse of $(x^i-x^j)$ modulo Cyclotomic Polynomial of the form \Phi _\{p^s\}(x) or \Phi _\{p^s q^t\}(x)},
  author={<NAME> and <NAME> <NAME> and <NAME>},
  journal={Journal of the Korean Mathematical Society (To Appear)},
  year={2021},
  manuscript={false},
  arxiv={2106.01742},
  abstract={The scaled inverse of a nonzero element $a(x)\in Z[x]/f(x)$, where $f(x)$ is an irreducible polynomial over $Z$, is the element $b(x)\in Z[x]/f(x)$ such that $a(x)b(x)=c mod f(x)$ for the smallest possible positive integer scale $c$. In this paper, we investigate the scaled inverse of $(x^i-x^j)$ modulo cyclotomic polynomial of the form $\Phi _\{p^s\}(x)$ or $\Phi _\{p^s q^t\}(x)$, where $p, q$ are primes with $p<q$ and $s, t$ are positive integers. Our main results are that the coefficient size of the scaled inverse of $(x^i-x^j)$ is bounded by $p-1$ with the scale $p$ modulo $\Phi _\{p^s\}(x)$, and is bounded by $q-1$ with the scale not greater than $q$ modulo $\Phi _\{p^s q^t\}(x)$. Previously, the analogous result on cyclotomic polynomials of the form $\Phi _\{2^n\}(x)$ gave rise to many lattice-based cryptosystems, especially, zero-knowledge proofs. Our result provides more flexible choice of cyclotomic polynomials in such cryptosystems. Along the way of proving the theorems, we also prove several properties of $\{x^k\}$ in $Z[x]/\Phi _\{pq\}(x)$ which might be of independent interest.}

}

@inproceedings{cheon2021mhz2k,
  abbr={Crypto},
  title={MHz2k: MPC from HE over Z2k with New Packing, Simpler Reshare, and Better ZKP},
  author={<NAME> and <NAME> and <NAME>},
  booktitle={Annual International Cryptology Conference},
  pages={426--456},
  organization={Springer},
  year={2021},
  manuscript={false},
  eprint = {2021/1383},
  video={https://youtu.be/Hi6pU7eT0k4},
  abstract={We propose a multi-party computation (MPC) protocol over Z2k secure against actively corrupted majority from somewhat homomorphic encryption. The main technical contributions are: (i) a new efficient packing method for Z2k-messages in lattice-based somewhat homomorphic encryption schemes, (ii) a simpler reshare protocol for level-dependent packings, (iii) a more efficient zero-knowledge proof of plaintext knowledge on cyclotomic rings $Z[X]/\Phi _M(X)$ with M being a prime. Integrating them, our protocol shows from 2.2x upto 4.8x improvements in amortized communication costs compared to the previous best results. Our techniques not only improve the efficiency of MPC over Z2k considerably, but also provide a toolkit that can be leveraged when designing other cryptographic primitives over Z2k.},
  slides={CKL21_slides.pdf}
}

@article{jung2021accelerating,
  abbr={IEEE Access},
  title={Accelerating Fully Homomorphic Encryption Through Architecture-Centric Analysis and Optimization},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME>},
  journal={IEEE Access},
  volume={9},
  pages={98772--98789},
  year={2021},
  publisher={IEEE},
  manuscript={false},
  arxiv={2003.04510},
  abstract={Homomorphic Encryption (HE) draws a significant attention as a privacy-preserving way for cloud computing because it allows computation on encrypted messages called ciphertexts. Among numerous HE schemes proposed, HE for Arithmetic of Approximate Numbers (HEAAN) is rapidly gaining popularity across a wide range of applications because it supports messages that can tolerate approximate computation with no limit on the number of arithmetic operations applicable to the corresponding ciphertexts. A critical shortcoming of HE is the high computation complexity of ciphertext arithmetic; especially, HE multiplication (HE Mul) is more than 10,000 times slower than the corresponding multiplication between unencrypted messages. This leads to a large body of HE acceleration studies, including ones exploiting FPGAs; however, those did not conduct a rigorous analysis of computational complexity and data access patterns of HE Mul. Moreover, the proposals mostly focused on designs with small parameter sizes, making it difficult to accurately estimate their performance in conducting a series of complex arithmetic operations. In this paper, we first describe how HE Mul of HEAAN is performed in a manner friendly to computer architects. Then we conduct a disciplined analysis on its computational and memory access characteristics, through which we (1) extract parallelism in the key functions composing HE Mul and (2) demonstrate how to effectively map the parallelism to the popular parallel processing platforms, multicore CPUs and GPUs, by applying a series of optimization techniques such as transposing matrices and pinning data to threads. This leads to the performance improvement of HE Mul on a CPU and a GPU by 42.9x and 134.1x, respectively, over the single-thread reference HEAAN running on a CPU. The conducted analysis and optimization would set a new foundation for future HE acceleration research.}
}

@inproceedings{kim2020hardware,
  abbr={FCCM},
  title={*Hardware Architecture of a Number Theoretic Transform for a Bootstrappable RNS-based Homomorphic Encryption Scheme},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME>},
  booktitle={2020 IEEE 28th Annual International Symposium on Field-Programmable Custom Computing Machines (FCCM)},
  pages={56--64},
  year={2020},
  organization={IEEE},
  manuscript={false}
}

@article{amors2020gimme,
  title={Gimme That Model!: A Trusted ML Model Trading Protocol},
  author={<NAME>, <NAME> <NAME> and Tol, <NAME>},
  journal={Protecting Privacy through Homomorphic Encryption},
  year={2021},
  book={true},
  arxiv={2003.00610},
  video={https://youtu.be/E8PPHkTQzYc},
  abstract={We propose a HE-based protocol for trading ML models and describe possible improvements to the protocol to make the overall transaction more efficient and secure.},
  url={https://link.springer.com/book/9783030772864}
}

@inproceedings{kim2019fpga,
  abbr={ReConFig},
  title={*FPGA-based Accelerators of Fully Pipelined Modular Multipliers for Homomorphic Encryption},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME> A},
  booktitle={2019 International Conference on ReConFigurable Computing and FPGAs (ReConFig)},
  pages={1--8},
  year={2019},
  organization={IEEE},
  manuscript={false}
}
@inproceedings{cheon2019numerical,
  abbr={Asiacrypt},
  title={Numerical method for comparison on homomorphically encrypted numbers},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME>},
  booktitle={International Conference on the Theory and Application of Cryptology and Information Security},
  pages={415--445},
  year={2019},
  organization={Springer, Cham},
  manuscript={false},
  eprint={2019/417}
}

@inproceedings{cheon2019efficient,
  abbr={ICISC},
  title={Efficient Identity-Based Encryption from LWR},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME>},
  booktitle={International Conference on Information Security and Cryptology},
  pages={225--241},
  year={2019},
  organization={Springer},
  manuscript={false}
}
@article{park2019secure,
  abbr={BMC},
  title={*A secure SNP panel scheme using homomorphically encrypted K-mers without SNP calling on the user side},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME> and <NAME> and Cheon, <NAME> and <NAME>},
  journal={BMC genomics},
  volume={20},
  number={2},
  pages={163--174},
  year={2019},
  publisher={BioMed Central},
  manuscript={false}
}
@article{kim2018logistic,
  abbr={BMC},
  title={*Logistic regression model training based on the approximate homomorphic encryption},
  author={<NAME> and <NAME> and <NAME> and <NAME> and <NAME>},
  journal={BMC medical genomics},
  volume={11},
  number={4},
  pages={23--31},
  year={2018},
  publisher={BioMed Central},
  manuscript={false},
  eprint={2018/254}
}

@inproceedings{cheon2017privacy,
  abbr={WAHC},
  title={Privacy-preserving computations of predictive medical models with minimax approximation and non-adjacent form},
  author={<NAME> and <NAME> and <NAME> and <NAME>},
  booktitle={International Conference on Financial Cryptography and Data Security},
  pages={53--74},
  year={2017},
  organization={Springer},
  manuscript={false}
}
