{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T16:14:48Z","timestamp":1778256888618,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T00:00:00Z","timestamp":1772409600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"EU Horizon Europe","award":["101114043"],"award-info":[{"award-number":["101114043"]}]},{"DOI":"10.13039\/501100006541","name":"Comunidad de Madrid","doi-asserted-by":"publisher","award":["PRTR-C17.I1"],"award-info":[{"award-number":["PRTR-C17.I1"]}],"id":[{"id":"10.13039\/501100006541","id-type":"DOI","asserted-by":"publisher"}]},{"name":"EuroQCI-Spain","award":["101091638"],"award-info":[{"award-number":["101091638"]}]},{"name":"Ministerio para la Transformaci\u00f3n Digital y de la Funci\u00f3n P\u00fablica","award":["PRTR-C16.R1"],"award-info":[{"award-number":["PRTR-C16.R1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Within the Madrid Quantum Communication Infrastructure (MadQCI), a cloud-like, quantum-enabled network scenario has been commissioned to promote the growth of the quantum technology scientific community. This scenario is designed to provide both quantum communication primitives and quantum-enabled services to potential end users. This work focuses on exposing these quantum services in a user-friendly manner by abstracting the underlying technical complexity, letting end users operate without prior knowledge of implementation details. To this end, multiple quantum services\u2014the SD-QKD software stack, QRNG, Quantum-Safe TLS, and Quantum-Safe IPsec as a Service\u2014are offered following the cloud \u201canything as a service\u201d (XaaS) model. The delivery of quantum-enabled services is therefore researched using an applied and transferable cloud-based paradigm.<\/jats:p>","DOI":"10.3390\/e28030283","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:06:56Z","timestamp":1772460416000},"page":"283","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The MadQCI Cloud Scenario: Quantum as a Service"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9502-9978","authenticated-orcid":false,"given":"Jaime S.","family":"Buruaga","sequence":"first","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7724-2911","authenticated-orcid":false,"given":"Alberto","family":"Sebasti\u00e1n-Lombra\u00f1a","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"},{"name":"DLSIIS, ETSI Inform\u00e1ticos, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3673-490X","authenticated-orcid":false,"given":"Ruben B.","family":"M\u00e9ndez","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6334-639X","authenticated-orcid":false,"given":"Rafael J.","family":"Vicente","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan P.","family":"Brito","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"},{"name":"DLSIIS, ETSI Inform\u00e1ticos, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3768-3998","authenticated-orcid":false,"given":"Laura","family":"Ortiz","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"},{"name":"DATSI, ETSI Inform\u00e1ticos, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2559-3979","authenticated-orcid":false,"given":"Vicente","family":"Martin","sequence":"additional","affiliation":[{"name":"Center for Computational Simulation, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"},{"name":"DLSIIS, ETSI Inform\u00e1ticos, Universidad Polit\u00e9cnica de Madrid, 28660 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1038\/s41534-024-00873-2","article-title":"MadQCI: A heterogeneous and scalable SDN-QKD network deployed in production facilities","volume":"10","author":"Martin","year":"2024","journal-title":"NPJ Quantum Inf."},{"key":"ref_2","unstructured":"Webster, J.G. 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