{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:52:55Z","timestamp":1785430375193,"version":"3.56.0"},"reference-count":43,"publisher":"International Association for Cryptologic Research","issue":"2","license":[{"start":{"date-parts":[[2025,1,14]],"date-time":"2025-01-14T00:00:00Z","timestamp":1736812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IACR CiC"],"accepted":{"date-parts":[[2025,6,2]]},"abstract":"<jats:p>Homomorphic encryption (HE) schemes have gained significant popularity in modern privacy-preserving applications across various domains. While research on HE constructions based on learning with errors (LWE) and ring-LWE has received major attention from both cryptographers and software-hardware designers alike, their module-LWE-based counterpart has remained comparatively under-explored in the literature. A recent work provides a module-LWE-based instantiation (MLWE-HE) of the Cheon-Kim-Kim-Song (CKKS) scheme and showcases several of its advantages such as parameter flexibility and improved parallelism. However, a primary limitation of this construction is the quadratic growth in the size of the relinearization keys. Our contribution is two-pronged: first, we present a new relinearization key-generation technique that addresses the issue of quadratic key size expansion by reducing it to linear growth. Second, we extend the application of MLWE-HE in a multi-group homomorphic encryption (MGHE) framework, thereby generalizing the favorable properties of the single-keyed HE to a multi-keyed setting as well as investigating additional flexibility attributes of the MGHE framework.<\/jats:p>","DOI":"10.62056\/ay7qjp10","type":"journal-article","created":{"date-parts":[[2025,7,7]],"date-time":"2025-07-07T17:09:09Z","timestamp":1751908149000},"update-policy":"https:\/\/doi.org\/10.62056\/adfjwm02dj","source":"Crossref","is-referenced-by-count":0,"title":["Revisiting Module Lattice-based Homomorphic Encryption and Application to Secure-MPC"],"prefix":"10.62056","volume":"2","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5565-5744","authenticated-orcid":false,"given":"Anisha","family":"Mukherjee","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00d7xrm67","id-type":"ROR","asserted-by":"publisher"}],"name":"Graz University of Technology","place":["Graz, 8010, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9805-5389","authenticated-orcid":false,"given":"Sujoy","family":"Roy","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00d7xrm67","id-type":"ROR","asserted-by":"publisher"}],"name":"Graz University of Technology","place":["Graz, 8010, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"48349","published-online":{"date-parts":[[2025,7,7]]},"reference":[{"key":"ref1:GENTRY09","isbn-type":"print","volume-title":"A Fully Homomorphic Encryption Scheme","author":"Craig Gentry","year":"2009","ISBN":"https:\/\/id.crossref.org\/isbn\/9781109444506"},{"key":"ref2:BV_11","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1109\/FOCS.2011.12","article-title":"Efficient Fully Homomorphic Encryption from (Standard) LWE","author":"Zvika Brakerski","year":"2011"},{"key":"ref3:DBLP:journals\/iacr\/FanV12","first-page":"144","article-title":"Somewhat Practical Fully Homomorphic Encryption","author":"Junfeng Fan","year":"2012","journal-title":"IACR Cryptol. ePrint Arch."},{"key":"ref4:DBLP:journals\/eccc\/BrakerskiGV11","first-page":"111","article-title":"Fully Homomorphic Encryption without Bootstrapping","author":"Zvika Brakerski","year":"2011","journal-title":"Electron. 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