{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:38:13Z","timestamp":1787027893847,"version":"build-2736575974"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,10,5]],"date-time":"2022-10-05T00:00:00Z","timestamp":1664928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"EU H2020 research and innovation programme","doi-asserted-by":"publisher","award":["952622"],"award-info":[{"award-number":["952622"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"EU H2020 research and innovation programme","doi-asserted-by":"publisher","award":["PID2020-116664RB-100"],"award-info":[{"award-number":["PID2020-116664RB-100"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000780","name":"EU H2020 research and innovation programme","doi-asserted-by":"publisher","award":["FPU20\/03008"],"award-info":[{"award-number":["FPU20\/03008"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"MCIN\/AEI\/10.13039\/501100011033","award":["952622"],"award-info":[{"award-number":["952622"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033","award":["PID2020-116664RB-100"],"award-info":[{"award-number":["PID2020-116664RB-100"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033","award":["FPU20\/03008"],"award-info":[{"award-number":["FPU20\/03008"]}]},{"name":"Andalusia Government","award":["952622"],"award-info":[{"award-number":["952622"]}]},{"name":"Andalusia Government","award":["PID2020-116664RB-100"],"award-info":[{"award-number":["PID2020-116664RB-100"]}]},{"name":"Andalusia Government","award":["FPU20\/03008"],"award-info":[{"award-number":["FPU20\/03008"]}]},{"name":"Spanish Government","award":["952622"],"award-info":[{"award-number":["952622"]}]},{"name":"Spanish Government","award":["PID2020-116664RB-100"],"award-info":[{"award-number":["PID2020-116664RB-100"]}]},{"name":"Spanish Government","award":["FPU20\/03008"],"award-info":[{"award-number":["FPU20\/03008"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cryptography"],"abstract":"<jats:p>The generation of unique identifiers extracted from the physical characteristics of the underlying hardware ensures the protection of electronic devices against counterfeiting and provides security to the data they store and process. This work describes the design of an efficient Physical Unclonable Function (PUF) based on the differences in the frequency of Ring Oscillators (ROs) with identical layout due to variations in the technological processes involved in the manufacture of the integrated circuit. The logic resources available in the Xilinx Series-7 programmable devices are exploited in the design to make it more compact and achieve an optimal bit-per-area rate. On the other hand, the design parameters can also be adjusted to provide a high bit-per-time rate for a particular target device. The PUF has been encapsulated as a configurable Intellectual Property (IP) module, providing it with an AXI4-Lite interface to ease its incorporation into embedded systems in combination with soft- or hard-core implementations of general-purpose processors. The capability of the proposed RO-PUF to generate implementation-dependent identifiers has been extensively tested, using a series of metrics to evaluate its reliability and robustness for different configuration options. Finally, in order to demonstrate its utility to improve system security, the identifiers provided by RO-PUFs implemented on different devices have been used in a Helper Data Algorithm (HDA) to obfuscate and retrieve a secret key.<\/jats:p>","DOI":"10.3390\/cryptography6040051","type":"journal-article","created":{"date-parts":[[2022,10,8]],"date-time":"2022-10-08T01:52:21Z","timestamp":1665193941000},"page":"51","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Efficient RO-PUF for Generation of Identifiers and Keys in Resource-Constrained Embedded Systems"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3025-5736","authenticated-orcid":false,"given":"Macarena C.","family":"Mart\u00ednez-Rodr\u00edguez","sequence":"first","affiliation":[{"name":"Instituto de Microelectr\u00f3nica de Sevilla, IMSE-CNM, CSIC\/Universidad de Sevilla, 41092 Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5568-1136","authenticated-orcid":false,"given":"Luis F.","family":"Rojas-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Instituto de Microelectr\u00f3nica de Sevilla, IMSE-CNM, CSIC\/Universidad de Sevilla, 41092 Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3177-2260","authenticated-orcid":false,"given":"Eros","family":"Camacho-Ruiz","sequence":"additional","affiliation":[{"name":"Instituto de Microelectr\u00f3nica de Sevilla, IMSE-CNM, CSIC\/Universidad de Sevilla, 41092 Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0700-0447","authenticated-orcid":false,"given":"Santiago","family":"S\u00e1nchez-Solano","sequence":"additional","affiliation":[{"name":"Instituto de Microelectr\u00f3nica de Sevilla, IMSE-CNM, CSIC\/Universidad de Sevilla, 41092 Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1059-5338","authenticated-orcid":false,"given":"Piedad","family":"Brox","sequence":"additional","affiliation":[{"name":"Instituto de Microelectr\u00f3nica de Sevilla, IMSE-CNM, CSIC\/Universidad de Sevilla, 41092 Sevilla, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2483","DOI":"10.1109\/JIOT.2017.2767291","article-title":"Evaluating Critical Security Issues of the IoT World: Present and Future Challenges","volume":"5","author":"Frustaci","year":"2018","journal-title":"IEEE Internet Things J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"8182","DOI":"10.1109\/JIOT.2019.2935189","article-title":"IoT: Internet of Threats? 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