{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,18]],"date-time":"2026-07-18T16:18:07Z","timestamp":1784391487984,"version":"3.55.0"},"reference-count":54,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T00:00:00Z","timestamp":1692230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"H2020 FISHY Project","doi-asserted-by":"publisher","award":["952644"],"award-info":[{"award-number":["952644"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"H2020 FISHY Project","doi-asserted-by":"publisher","award":["PID2019-108713RB681"],"award-info":[{"award-number":["PID2019-108713RB681"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"H2020 FISHY Project","doi-asserted-by":"publisher","award":["MCIN\/AEI\/10.13039\/5011000110"],"award-info":[{"award-number":["MCIN\/AEI\/10.13039\/5011000110"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"TRUE5G project","award":["952644"],"award-info":[{"award-number":["952644"]}]},{"name":"TRUE5G project","award":["PID2019-108713RB681"],"award-info":[{"award-number":["PID2019-108713RB681"]}]},{"name":"TRUE5G project","award":["MCIN\/AEI\/10.13039\/5011000110"],"award-info":[{"award-number":["MCIN\/AEI\/10.13039\/5011000110"]}]},{"name":"Spanish National Research Agency","award":["952644"],"award-info":[{"award-number":["952644"]}]},{"name":"Spanish National Research Agency","award":["PID2019-108713RB681"],"award-info":[{"award-number":["PID2019-108713RB681"]}]},{"name":"Spanish National Research Agency","award":["MCIN\/AEI\/10.13039\/5011000110"],"award-info":[{"award-number":["MCIN\/AEI\/10.13039\/5011000110"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>Microservices have become promising candidates for the deployment of network and vertical functions in the fifth generation of mobile networks. However, microservice platforms like Kubernetes use a flat networking approach towards the connectivity of virtualised workloads, which prevents the deployment of network functions on isolated network segments (for example, the components of an IP Telephony system or a content distribution network). This paper presents L2S-M, a solution that enables the connectivity of Kubernetes microservices over isolated link-layer virtual networks, regardless of the compute nodes where workloads are actually deployed. L2S-M uses software-defined networking (SDN) to fulfil this purpose. Furthermore, the L2S-M design is flexible to support the connectivity of Kubernetes workloads across different Kubernetes clusters. We validate the functional behaviour of our solution in a moderately complex Smart Campus scenario, where L2S-M is used to deploy a content distribution network, showing its potential for the deployment of network services in distributed and heterogeneous environments.<\/jats:p>","DOI":"10.3390\/fi15080274","type":"journal-article","created":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T10:42:29Z","timestamp":1692268949000},"page":"274","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Link-Layer Virtual Networking Solution for Cloud-Native Network Function Virtualisation Ecosystems: L2S-M"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0465-854X","authenticated-orcid":false,"given":"Luis F.","family":"Gonzalez","sequence":"first","affiliation":[{"name":"Telematic Engineering Department, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7381-971X","authenticated-orcid":false,"given":"Ivan","family":"Vidal","sequence":"additional","affiliation":[{"name":"Telematic Engineering Department, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5056-0573","authenticated-orcid":false,"given":"Francisco","family":"Valera","sequence":"additional","affiliation":[{"name":"Telematic Engineering Department, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raul","family":"Martin","sequence":"additional","affiliation":[{"name":"Telematic Engineering Department, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0711-6362","authenticated-orcid":false,"given":"Dulce","family":"Artalejo","sequence":"additional","affiliation":[{"name":"Telematic Engineering Department, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Legan\u00e9s, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,17]]},"reference":[{"key":"ref_1","unstructured":"Cloud Native Computing Foundation (2023, June 11). Building Sustainable Ecosystems for Cloud Native Software. Available online: https:\/\/www.cncf.io."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Liu, G., Huang, B., Liang, Z., Qin, M., Zhou, H., and Li, Z. (2020, January 11\u201314). Microservices: Architecture, container, and challenges. 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