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A guide to homomorphic encryption

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Abstract

Traditional cryptography techniques require our data to be unencrypted to be processed correctly. This means that at some stage on a system we have no control over, our data will be processed in plaintext. Homomorphic encryption or specifically, fully homomorphic encryption is a viable solution to this problem. It allows encrypted data to be processed as if it were in plaintext and will produce the correct value once decrypted. While many know that homomorphic encryption promises to be an ideal solution to trust, security, and privacy issues in cloud computing, few actually knows how it works and why it is not yet a practical solution despite its promises. This chapter serves as a much needed primer on current homomorphic encryption techniques, discusses about several practical challenges, and introduces workarounds proposed by practitioners and researchers to overcome these challenges.

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... Rivest et al., 1978 was the first to explore the design of a homomorphic encryption scheme. Acar et al., 2018;Armknecht et al., 2015;Gentry, 2009. In the next section, we will provide an overview of homomorphic encryption schemes. ...
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