{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,19]],"date-time":"2025-11-19T07:06:15Z","timestamp":1763535975599,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,5,23]],"date-time":"2022-05-23T00:00:00Z","timestamp":1653264000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DAWN4IoE - Data Aware Wireless Network for Internet-of-Everything","award":["778305"],"award-info":[{"award-number":["778305"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The proliferation of low-cost Internet of Things (IoT) devices has led to a race between wireless security and channel attacks. Traditional cryptography requires high computational power and is not suitable for low-power IoT scenarios. Whilst recently developed physical layer security (PLS) can exploit common wireless channel state information (CSI), its sensitivity to channel estimation makes them vulnerable to attacks. In this work, we exploit an alternative common physics shared between IoT transceivers: the monitored channel-irrelevant physical networked dynamics (e.g., water\/oil\/gas\/electrical signal-flows). Leveraging this, we propose, for the first time, graph layer security (GLS), by exploiting the dependency in physical dynamics among network nodes for information encryption and decryption. A graph Fourier transform (GFT) operator is used to characterise such dependency into a graph-bandlimited subspace, which allows the generation of channel-irrelevant cipher keys by maximising the secrecy rate. We evaluate our GLS against designed active and passive attackers, using IEEE 39-Bus system. Results demonstrate that GLS is not reliant on wireless CSI, and can combat attackers that have partial networked dynamic knowledge (realistic access to full dynamic and critical nodes remains challenging). We believe this novel GLS has widespread applicability in secure health monitoring and for digital twins in adversarial radio environments.<\/jats:p>","DOI":"10.3390\/s22103951","type":"journal-article","created":{"date-parts":[[2022,5,25]],"date-time":"2022-05-25T00:14:14Z","timestamp":1653437654000},"page":"3951","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Graph Layer Security: Encrypting Information via Common Networked Physics"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8073-7859","authenticated-orcid":false,"given":"Zhuangkun","family":"Wei","sequence":"first","affiliation":[{"name":"School of Aerospace, Transport and Manufacturing, Cranfield University, Bedford MK43 0AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liang","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Aerospace, Transport and Manufacturing, Cranfield University, Bedford MK43 0AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Schyler Chengyao","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Aerospace, Transport and Manufacturing, Cranfield University, Bedford MK43 0AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bin","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weisi","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Aerospace, Transport and Manufacturing, Cranfield University, Bedford MK43 0AL, UK"},{"name":"The Alan Turing Institute, London NW1 2DB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1109\/MIC.2016.124","article-title":"Internet of Things for Smart Cities: Interoperability and Open Data","volume":"20","author":"Ahlgren","year":"2016","journal-title":"IEEE Internet Comput."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1109\/MCC.2015.14","article-title":"Processing Distributed Internet of Things Data in Clouds","volume":"2","author":"Wang","year":"2015","journal-title":"IEEE Cloud Comput."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3443","DOI":"10.1109\/COMST.2019.2934365","article-title":"Toward the Internet of Underground Things: A Systematic Survey","volume":"21","author":"Saeed","year":"2019","journal-title":"IEEE Commun. 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