{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T18:49:22Z","timestamp":1764874162628,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,10,14]],"date-time":"2024-10-14T00:00:00Z","timestamp":1728864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Eng"],"abstract":"<jats:p>This paper presents an efficient and secure method for updating firmware in IoT devices using LoRaWAN network resources and communication protocols. The proposed method involves dividing the firmware into fragments, storing them in the application server\u2019s database, and transmitting them to remote IoT devices via downlink messages, without necessitating any changes to the device\u2019s class. This approach can be replicated across any IoT LoRaWAN device, offering a robust and scalable solution for large-scale firmware updates while ensuring data security and integrity. The proposed method significantly reduces the downtime of IoT devices and enhances the energy efficiency of the update process. The method was validated by updating a block in the program memory, associated to a specific functionality of the IoT end device. The associated Intel Hex file was segmented into 17 LoRaWAN downlink frames with an average size of 46 bytes. Upon receiving the complete firmware update, the microcontroller employs self-programming techniques that restrict the update process to specific rows of the program memory, avoiding interruptions or reboots. The update process was successfully completed in 51.33 ms, resulting in a downtime of 16.88 ms. This method demonstrates improved energy efficiency compared to existing solutions while preserving the communication network\u2019s capacity, making it an adequate solution for remote devices in LoRaWAN networks.<\/jats:p>","DOI":"10.3390\/eng5040137","type":"journal-article","created":{"date-parts":[[2024,10,17]],"date-time":"2024-10-17T11:19:18Z","timestamp":1729163958000},"page":"2610-2632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Efficient Runtime Firmware Update Mechanism for LoRaWAN Class A Devices"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9018-5859","authenticated-orcid":false,"given":"Bernardino Pinto","family":"Neves","sequence":"first","affiliation":[{"name":"Engineering Department, School of Sciences and Technology, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal"},{"name":"ENEIDA, Grid Intelligence, S.A., Rua Alexandre Herculano 21B, 3000-019 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5798-1298","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Valente","sequence":"additional","affiliation":[{"name":"Engineering Department, School of Sciences and Technology, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal"},{"name":"INESC Technology and Science, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5441-4394","authenticated-orcid":false,"given":"Victor D. N.","family":"Santos","sequence":"additional","affiliation":[{"name":"Polytechnic Institute of Coimbra, Coimbra Institute of Engineering, Rua Pedro Nunes-Quinta da Nora, 3030-199 Coimbra, Portugal"},{"name":"INESC Coimbra, DEEC, Polo II, 3030-290 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,14]]},"reference":[{"key":"ref_1","unstructured":"Jongboom, J., and Stokking, J. (March, January 27). Enabling firmware updates over LPWANs. Proceedings of the Embedded World Conference, Nuremberg, Germany. Available online: https:\/\/scholar.google.com\/scholar_lookup?title=Enabling+firmware+updates+over+LPWANs&conference=Proceedings+of+the+Embedded+World+Conference&author=Jongboom,+J.&author=Stokking,+J.&publication_year=2018."},{"key":"ref_2","unstructured":"Sch\u00e4fer, B. (2024, June 09). LoRaWAN Firmware Update Over The Air\u2014FUOTA. 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Proceedings of the 2022 International Conference on Information Networking (ICOIN), Jeju-si, Republic of Korea.","DOI":"10.1109\/ICOIN53446.2022.9687242"}],"container-title":["Eng"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2673-4117\/5\/4\/137\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:12:54Z","timestamp":1760112774000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2673-4117\/5\/4\/137"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,14]]},"references-count":23,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["eng5040137"],"URL":"https:\/\/doi.org\/10.3390\/eng5040137","relation":{},"ISSN":["2673-4117"],"issn-type":[{"type":"electronic","value":"2673-4117"}],"subject":[],"published":{"date-parts":[[2024,10,14]]}}}