Abstract
Inverse sqrt and sqrt function have numerous applications in linear algebra and machine learning such as vector normalisation, eigenvalue computation, dimensionality reduction, clustering, etc. This paper presents a method to approximate and securely perform the inverse sqrt function using CKKS homomorphic encryption scheme. Since the CKKS homomorphic scheme allows only computation of polynomial functions, we propose a method to approximate the inverse sqrt function polynomially. In the end, we provide an implementation of our method for the inverse sqrt function.
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Notes
- 1.
We consider non-scalar multiplicative depth i.e. ciphertext-ciphertext multiplication.
- 2.
By convergence we mean that the difference between the actual and predicted value is bounded by some predefined error.
References
Boemer, F., Costache, A., Cammarota, R., Wierzynski, C.: Ngraph-he2: a high-throughput framework for neural network inference on encrypted data. In: Proceedings of the 7th ACM Workshop on Encrypted Computing and Applied Homomorphic Cryptography, pp. 45–56. WAHC 2019, Association for Computing Machinery, New York, NY, USA (2019). https://doi.org/10.1145/3338469.3358944
Boura, C., Gama, N., Georgieva, M., Jetchev, D.: Chimera: combining ring-LWE-based fully homomorphic encryption schemes. Cryptology ePrint Archive, Report 2018/758 (2018). https://eprint.iacr.org/2018/758
Cheon, J.H., Kim, A., Kim, M., Song, Y.: Homomorphic encryption for arithmetic of approximate numbers. Cryptology ePrint Archive, Report 2016/421 (2016). https://eprint.iacr.org/2016/421
Cheon, J.H., Kim, D., Kim, D.: Efficient homomorphic comparison methods with optimal complexity. Cryptology ePrint Archive, Report 2019/1234 (2019). https://ia.cr/2019/1234
Han, K., Hong, S., Cheon, J.H., Park, D.: Efficient logistic regression on large encrypted data. Cryptology ePrint Archive, Report 2018/662 (2018). https://eprint.iacr.org/2018/662
Lee, J.W., et al.: Privacy-preserving machine learning with fully homomorphic encryption for deep neural network. Cryptology ePrint Archive, Report 2021/783 (2021). https://ia.cr/2021/783
Lomont, C.: Fast inverse square root. Technical report Purdue University (2003). http://www.matrix67.com/data/InvSqrt.pdf
Lu, W., Huang, Z., Hong, C., Ma, Y., Qu, H.: Pegasus: bridging polynomial and non-polynomial evaluations in homomorphic encryption. In: 2021 IEEE Symposium on Security and Privacy (S&P), pp. 1057–1073. IEEE Computer Society, Los Alamitos, CA, USA, May 2021. https://doi.org/10.1109/SP40001.2021.00043
Panda, S.: Principal component analysis using CKKS homomorphic encryption scheme. Cyber Security Cryptography and Machine Learning, 5th International Symposium, CSCML 2021 (2021). https://eprint.iacr.org/2021/914
Panda, S.: Pivot-tangent method. https://github.com/pandasamanvaya/Pivot-tangent (2022)
Microsoft SEAL (release 3.7), Microsoft Research, Redmond, WA, September 2021. https://github.com/Microsoft/SEAL
Tasissa, A.: Function approximation and the Remez algorithm (2019)
Trefethen, L.N.: Approximation Theory and Approximation Practice. Extended Edition. SIAM (2019)
Çetin, G.S., Doröz, Y., Sunar, B., Martin, W.J.: Arithmetic using word-wise homomorphic encryption (2016)
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Panda, S. (2022). Polynomial Approximation of Inverse sqrt Function for FHE. In: Dolev, S., Katz, J., Meisels, A. (eds) Cyber Security, Cryptology, and Machine Learning. CSCML 2022. Lecture Notes in Computer Science, vol 13301. Springer, Cham. https://doi.org/10.1007/978-3-031-07689-3_27
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DOI: https://doi.org/10.1007/978-3-031-07689-3_27
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