{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T05:32:28Z","timestamp":1782970348886,"version":"3.54.5"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,3,2]],"date-time":"2023-03-02T00:00:00Z","timestamp":1677715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union under the Italian National Recovery and Resilience Plan (NRRP) of NextGenerationEU, partnership on \u201cTelecommunications of the Future\u201d","award":["PE00000001"],"award-info":[{"award-number":["PE00000001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Reconfigurable intelligent surfaces (RIS) are considered of paramount importance to improve air\u2013ground and THz communications performance for 6G systems. Recently, RISs were proposed in Physical Layer Security (PLS), as they can (i) improve the secrecy capacity due to the controlled directional reflections\u2019 capability of RIS elements and (ii) avoid potential eavesdroppers, redirecting data streams towards the intended users. This paper proposes the integration of a multi-RISs system within a Software Defined Networking (SDN) architecture to provide a specific control layer for secure data flows forwarding. The optimisation problem is properly characterised in terms of an objective function and an equivalent graph theory model is considered to address the optimal solution. Moreover, different heuristics are proposed, trading off complexity and PLS performance, to evaluate the more suitable multi-beam routing strategy. Numerical results are also provided, focusing on a worst case scenario which points out the improvement of the secrecy rate from the increase in the number of eavesdroppers. Furthermore, the security performance is investigated for a specific user mobility pattern in a pedestrian scenario.<\/jats:p>","DOI":"10.3390\/s23052726","type":"journal-article","created":{"date-parts":[[2023,3,2]],"date-time":"2023-03-02T03:06:43Z","timestamp":1677726403000},"page":"2726","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Secure Networking with Software-Defined Reconfigurable Intelligent Surfaces"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0267-4733","authenticated-orcid":false,"given":"Francesco","family":"Chiti","sequence":"first","affiliation":[{"name":"Department of Information Engineering, University of Florence, 50139 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9122-2945","authenticated-orcid":false,"given":"Ashley","family":"Degl\u2019Innocenti","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Florence, 50139 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6271-7988","authenticated-orcid":false,"given":"Laura","family":"Pierucci","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Florence, 50139 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1109\/MCOM.001.1900107","article-title":"Towards Smart and Reconfigurable Environment: Intelligent Reflecting Surface Aided Wireless Network","volume":"58","author":"Wu","year":"2020","journal-title":"IEEE Commun. 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