{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T19:20:05Z","timestamp":1777663205614,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T00:00:00Z","timestamp":1767830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011033","name":"Spanish State Research Agency","doi-asserted-by":"publisher","award":["PID2022-137329OB-C42"],"award-info":[{"award-number":["PID2022-137329OB-C42"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100018693","name":"Horizon Europe programme","doi-asserted-by":"publisher","award":["101070118"],"award-info":[{"award-number":["101070118"]}],"id":[{"id":"10.13039\/100018693","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100018693","name":"Horizon Europe programme","doi-asserted-by":"publisher","award":["101168182"],"award-info":[{"award-number":["101168182"]}],"id":[{"id":"10.13039\/100018693","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>Connecting distributed applications across multiple cloud-native domains is growing in complexity. Applications have become containerized and fragmented across heterogeneous infrastructures, such as public clouds, edge nodes, and private data centers, including emerging IoT-driven environments. Existing networking solutions like CNI plugins and service meshes have proven insufficient for providing isolated, low-latency and secure multi-cluster communication. By combining SDN control with Kubernetes abstractions, we present L2S-CES, a Kubernetes-native solution for multi-cluster layer-2 network slicing that offers flexible isolated connectivity for microservices while maintaining performance and automation. In this work, we detail the design and implementation of L2S-CES, outlining its architecture and operational workflow. We experimentally validate against state-of-the-art alternatives and show superior isolation, reduced setup time, native support for broadcast and multicast, and minimal performance overhead. By addressing the current lack of native link-layer networking capabilities across multiple Kubernetes domains, L2S-CES provides a unified and practical foundation for deploying scalable, multi-tenant, and latency-sensitive cloud-native applications.<\/jats:p>","DOI":"10.3390\/fi18010039","type":"journal-article","created":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T14:32:38Z","timestamp":1767882758000},"page":"39","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Architecting Multi-Cluster Layer-2 Connectivity for Cloud-Native Network Slicing"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-2388-7562","authenticated-orcid":false,"given":"Alex T. de Cock","family":"Buning","sequence":"first","affiliation":[{"name":"Department of Telematic Engineering, Escuela Polit\u00e9cnica Superior, Universidad Carlos III de Madrid (UC3M), Avda. de la Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7381-971X","authenticated-orcid":false,"given":"Ivan","family":"Vidal","sequence":"additional","affiliation":[{"name":"Department of Telematic Engineering, Escuela Polit\u00e9cnica Superior, Universidad Carlos III de Madrid (UC3M), Avda. de la Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5056-0573","authenticated-orcid":false,"given":"Francisco","family":"Valera","sequence":"additional","affiliation":[{"name":"Department of Telematic Engineering, Escuela Polit\u00e9cnica Superior, Universidad Carlos III de Madrid (UC3M), Avda. de la Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3690","DOI":"10.1109\/OJCOMS.2024.3414622","article-title":"An in-depth survey on virtualization technologies in 6G integrated terrestrial and non-terrestrial networks","volume":"5","author":"Ammar","year":"2024","journal-title":"IEEE Open J. 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