Dynamic Decentralized Functional Encryption Article Swipe
YOU?
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· 2020
· Open Access
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· DOI: https://doi.org/10.5281/zenodo.3949877
· OA: W4287867687
<strong>Accepted paper for the CRYPTO 2020 conference</strong> <strong>[Abstract] </strong>We introduce <strong>Dynamic Decentralized Functional Encryption (DDFE)</strong>, a generalization of <strong>Functional Encryption</strong> which allows multiple users to join the system dynamically, without relying on a trusted third party or on expensive and interactive <strong>Multi-Party Computation protocols</strong>. This notion subsumes existing <strong>multi-user extensions of Functional Encryption</strong>, such as <strong>Multi-Input</strong>, <strong>Multi-Client</strong>, and A<strong>d Hoc Multi-Input Functional Encryption</strong>. We define and construct schemes for various functionalities which serve as building-blocks for latter primitives and may be useful in their own right, such as a scheme for dynamically computing sums in any Abelian group. These constructions build upon simple primitives in a modular way, and have instantiations from well-studied assumptions, such as DDH or LWE. Our constructions culminate in an <strong>Inner-Product scheme</strong> for computing weighted sums on aggregated encrypted data, from standard assumptions in prime-order groups in the <strong>Random Oracle Model</strong>.
