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This approach has many practical applications. First and foremost, it becomes an integral tool for the recent standardization initiatives of homomorphic schemes and common APIs. Then, it can be used in many real-life scenarios where operations of different nature and not achievable within a single FHE scheme have to be performed and where it is important to efficiently switch from one scheme to another. Finally, as a byproduct of our analysis we introduce the notion of a FHE module structure, that generalizes the notion of the external product, but can certainly be of independent interest in future research in FHE.<\/jats:p>","DOI":"10.1515\/jmc-2019-0026","type":"journal-article","created":{"date-parts":[[2020,8,17]],"date-time":"2020-08-17T06:30:07Z","timestamp":1597645807000},"page":"316-338","source":"Crossref","is-referenced-by-count":84,"title":["CHIMERA: Combining Ring-LWE-based Fully Homomorphic Encryption Schemes"],"prefix":"10.1515","volume":"14","author":[{"given":"Christina","family":"Boura","sequence":"first","affiliation":[{"name":"Laboratoire de Math\u00e9matiques de Versailles, UVSQ, CNRS , Universit\u00e9 Paris-Saclay , Versailles , France"},{"name":"Inria , Paris , France"}]},{"given":"Nicolas","family":"Gama","sequence":"additional","affiliation":[{"name":"Inpher , Lausanne , Switzerland"},{"name":"Laboratoire de Math\u00e9matiques de Versailles, UVSQ, CNRS , Universit\u00e9 Paris-Saclay , Versailles , France"}]},{"given":"Mariya","family":"Georgieva","sequence":"additional","affiliation":[{"name":"Inpher , Lausanne , Switzerland"},{"name":"EPFL , Lausanne , Switzerland"}]},{"given":"Dimitar","family":"Jetchev","sequence":"additional","affiliation":[{"name":"Inpher , Lausanne , Switzerland"},{"name":"EPFL , Lausanne , Switzerland"}]}],"member":"374","published-online":{"date-parts":[[2020,8,7]]},"reference":[{"key":"2025120600172410132_j_jmc-2019-0026_ref_001_w2aab3b7e1350b1b6b1ab2ab1Aa","unstructured":"Track 2: Secure parallel genome wide association studies using homomorphic encryption. www.humangenomeprivacy.org\/2018\/competition-tasks.html, 2018."},{"key":"2025120600172410132_j_jmc-2019-0026_ref_002_w2aab3b7e1350b1b6b1ab2ab2Aa","unstructured":"M. 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