{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T18:52:16Z","timestamp":1781203936954,"version":"3.54.1"},"reference-count":37,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,10]],"date-time":"2021-09-10T00:00:00Z","timestamp":1631232000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Functional safety networks are becoming of paramount importance in industrial systems, due to the progressive innovation introduced by the Industry 4.0 paradigm, characterized by high production flexibility, reliability and scalability. In this context, new and challenging applications have emerged such as hyperautomation, which refers to the combination of machine vision, robotics, communication, and learning, with the explicit involvement of humans. This requires the pervasive and ubiquitous connectivity encompassed by the Industrial Internet of Things, typically achieved via wireless systems. As an example, wireless communications are today fundamental to open up to new categories of autonomous devices that can actively collaborate with human personnel in the production process. This challenging scenario has important implications for safety. Indeed, a reliable coordination among sensors, actuators and computing systems is required to provide satisfactory levels of safety, especially in the case of innovative processes and technologies, such as mobile and collaborative robotics. Hence, it becomes imperative to ensure the correct transfer of safety-critical data via communication networks. In this paper, we address the challenges concerned with functional safety networks and protocols in Industrial Internet of Things ecosystems. We first introduce the design characteristics of functional safety networks and discuss the adoption of safety protocols over wireless networks. Then, we specifically address one of such protocols, namely Fail Safety over EtherCAT (FSoE), and provide the results of an extensive experimental session carried out exploiting a prototype system, implemented using commercial devices based on a WiFi network. Finally, the outcomes of the experiments are used as a basis for a discussion about future trends of functional safety in the Industrial Internet of Things era.<\/jats:p>","DOI":"10.3390\/s21186073","type":"journal-article","created":{"date-parts":[[2021,9,12]],"date-time":"2021-09-12T21:48:01Z","timestamp":1631483281000},"page":"6073","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Functional Safety Networks and Protocols in the Industrial Internet of Things Era"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5444-6946","authenticated-orcid":false,"given":"Giovanni","family":"Peserico","sequence":"first","affiliation":[{"name":"Department of Information Engineering, University of Padova, 35131 Padova, Italy"},{"name":"Autec s.r.l., 36030 Caldogno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Morato","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Padova, 35131 Padova, Italy"},{"name":"C.M.Z. Sistemi Elettronici s.r.l., 31050 Treviso, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6380-7897","authenticated-orcid":false,"given":"Federico","family":"Tramarin","sequence":"additional","affiliation":[{"name":"Department of Engineering \u201cEnzo Ferrari\u201d, University of Modena and Reggio Emilia, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3859-3510","authenticated-orcid":false,"given":"Stefano","family":"Vitturi","sequence":"additional","affiliation":[{"name":"National Research Council of Italy, CNR-IEIIT, 35131 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,10]]},"reference":[{"key":"ref_1","unstructured":"(2016). IEC 61508: Functional Safety of Electrical\/Electronic\/Programmable Electronic Safety-Related Systems, International Electrotechnical Commission. Standard."},{"key":"ref_2","unstructured":"(2021, September 09). Mordor Intelligence: Functional Safety Market\u2013Growth, Trends, and Forecasts (2020\u20132025). Available online: https:\/\/www.mordorintelligence.com\/industry-reports\/functional-safety-market."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1109\/MIE.2012.2207815","article-title":"Dependability and Functional Safety: Applications in Industrial Electronics Systems","volume":"6","author":"Buja","year":"2012","journal-title":"IEEE Ind. Electron. Mag."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"944","DOI":"10.1109\/JPROC.2019.2913443","article-title":"Industrial Communication Systems and Their Future Challenges: Next-Generation Ethernet, IIoT, and 5G","volume":"107","author":"Vitturi","year":"2019","journal-title":"Proc. IEEE"},{"key":"ref_5","first-page":"1","article-title":"Industry 4.0: A Survey on Technologies, Applications and Open Research Issues","volume":"6","author":"Lu","year":"2017","journal-title":"J. Ind. Inf. Integr."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1109\/MIE.2019.2947119","article-title":"Why We Need Automation Models: Handling Complexity in Industry 4.0 and the Internet of Things","volume":"14","author":"Jasperneite","year":"2020","journal-title":"IEEE Ind. Electron. Mag."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"4724","DOI":"10.1109\/TII.2018.2852491","article-title":"Industrial Internet of Things: Challenges, Opportunities, and Directions","volume":"14","author":"Sisinni","year":"2018","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"134498","DOI":"10.1109\/ACCESS.2020.3011483","article-title":"A Systematic Literature Study on Definition and Modeling of Service-Level Agreements for Cloud Services in IoT","volume":"8","author":"Girs","year":"2020","journal-title":"IEEE Access"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1109\/MIE.2016.2618724","article-title":"Massive Internet of Things for Industrial Applications: Addressing Wireless IIoT Connectivity Challenges and Ecosystem Fragmentation","volume":"11","author":"Mumtaz","year":"2017","journal-title":"IEEE Ind. Electron. Mag."},{"key":"ref_10","first-page":"4580","article-title":"Enhancing functional safety in FPGA-based motor drives","volume":"2019","author":"Jeppesen","year":"2019","journal-title":"J. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"4378","DOI":"10.1109\/TIE.2017.2762621","article-title":"Fast Functional Safety Verification for Distributed Automotive Applications During Early Design Phase","volume":"65","author":"Xie","year":"2018","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5629","DOI":"10.1109\/TII.2020.2978889","article-title":"Recent Advances and Future Trends for Automotive Functional Safety Design Methodologies","volume":"16","author":"Xie","year":"2020","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1109\/TNS.2020.2972903","article-title":"Qualification of Hardware Description Language Designs for Safety Critical Applications in Nuclear Power Plants","volume":"67","author":"John","year":"2020","journal-title":"IEEE Trans. Nucl. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Robinson, S.H. (2019, January 1\u20132). Living with the challenges to functional safety in the industrial Internet of Things. Proceedings of the Living in the Internet of Things (IoT 2019), London, UK.","DOI":"10.1049\/cp.2019.0160"},{"key":"ref_15","unstructured":"(2016). Industrial Communication Networks-Profiles-Part 3: Functional Safety Fieldbuses-General Rules and Profile Definitions, International Electrotechnical Commission. IEC 61784-3."},{"key":"ref_16","unstructured":"(2019). OPC Unified Architecture Part 15: Safety, OPC Foundation. Standard."},{"key":"ref_17","unstructured":"(2010). Industrial Communications Subsystem Based on ISO 11898 (CAN) for Controller-Device Interfaces\u2013Part 5: Functional Safety Communication Based on EN 50325\u20134, European Committee for Electrotechnical Standardization (CENELEC). Standard."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3513","DOI":"10.1109\/TII.2018.2829899","article-title":"Safe-WirelessHART: A Novel Framework Enabling Safety-Critical Applications over Industrial WSNs","volume":"14","author":"Yang","year":"2018","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Morato, A., Vitturi, S., Cenedese, A., Fadel, G., and Tramarin, F. (2019, January 10\u201313). The Fail Safe over EtherCAT (FSoE) Protocol Implemented on the IEEE 802.11 WLAN. Proceedings of the 2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA), Zaragoza, Spain.","DOI":"10.1109\/ETFA.2019.8869503"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4279","DOI":"10.1109\/TIE.2009.2017098","article-title":"Integration of a Wireless IO Interface for PROFIBUS and PROFINET for Factory Automation","volume":"56","author":"Kjellsson","year":"2009","journal-title":"Ind. Electron. IEEE Trans."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2607","DOI":"10.1109\/JSEN.2018.2793946","article-title":"A Delay-Bounded MAC Protocol for Mission- and Time-Critical Applications in Industrial Wireless Sensor Networks","volume":"18","author":"Farag","year":"2018","journal-title":"IEEE Sens. J."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1053","DOI":"10.1109\/JPROC.2019.2897627","article-title":"WIA-FA and Its Applications to Digital Factory: A Wireless Network Solution for Factory Automation","volume":"107","author":"Liang","year":"2019","journal-title":"Proc. IEEE"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3104","DOI":"10.1109\/TIM.2009.2016882","article-title":"Monitoring in Industrial Systems Using Wireless Sensor Network With Dynamic Power Management","volume":"58","author":"Salvadori","year":"2009","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4651","DOI":"10.1109\/TIE.2009.2028349","article-title":"Online and Remote Motor Energy Monitoring and Fault Diagnostics Using Wireless Sensor Networks","volume":"56","author":"Lu","year":"2009","journal-title":"IEEE Trans. Ind. Electron."},{"key":"ref_25","unstructured":"(2016). Industrial Communication Networks-Profiles-Part 3-3: Functional Safety Fieldbuses-Additional Specifications for CPF 3, International Electrotechnical Commission. Standard."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1186\/1687-1499-2011-100","article-title":"Efficient Integration of Secure and Safety Critical Industrial Wireless Sensor Networks","volume":"2011","author":"Gidlund","year":"2011","journal-title":"EURASIP J. Wirel. Commun. Netw."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Pimentel, V., and Nickerson, B.G. (November, January 29). A Safety Function Response Time Model for Wireless Industrial Control. Proceedings of the IECON 2014-40th Annual Conference of the IEEE Industrial Electronics Society, Dallas, TX, USA.","DOI":"10.1109\/IECON.2014.7049079"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1130","DOI":"10.1109\/JPROC.2005.849717","article-title":"Wireless Technology in Industrial Networks","volume":"93","author":"Willig","year":"2005","journal-title":"Proc. IEEE"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TIM.2020.3043116","article-title":"Assessment of Different OPC UA Implementations for Industrial IoT-Based Measurement Applications","volume":"70","author":"Morato","year":"2021","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1109\/MCOM.2018.1701178","article-title":"Ultra-Reliable Low Latency Cellular Networks: Use Cases, Challenges and Approaches","volume":"56","author":"Chen","year":"2018","journal-title":"IEEE Commun. Mag."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2618","DOI":"10.1109\/TII.2018.2799177","article-title":"Energy-Efficient Resource Allocation for Industrial Cyber-Physical IoT Systems in 5G Era","volume":"14","author":"Li","year":"2018","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1109\/MNET.2018.1700232","article-title":"5G Radio Network Design for Ultra-Reliable Low-Latency Communication","volume":"32","author":"Sachs","year":"2018","journal-title":"IEEE Netw."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1132","DOI":"10.1109\/JPROC.2019.2903414","article-title":"Extending Accurate Time Distribution and Timeliness Capabilities over the Air to Enable Future Wireless Industrial Automation Systems","volume":"107","author":"Cavalcanti","year":"2019","journal-title":"Proc. IEEE"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1109\/TII.2012.2198666","article-title":"Review of Security Issues in Industrial Networks","volume":"9","author":"Cheminod","year":"2013","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"89821","DOI":"10.1109\/ACCESS.2019.2926650","article-title":"Research on Safe Communication Architecture for Real-Time Ethernet Distributed Control System","volume":"7","author":"Huang","year":"2019","journal-title":"IEEE Access"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1109\/JPROC.2019.2913450","article-title":"Real-Time and Reliable Industrial Control over Wireless LANs: Algorithms, Protocols, and Future Directions","volume":"107","author":"Tramarin","year":"2019","journal-title":"Proc. IEEE"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"846","DOI":"10.1109\/TII.2016.2616327","article-title":"A Dynamic Rate Selection Algorithm for IEEE 802.11 Industrial Wireless LAN","volume":"13","author":"Tramarin","year":"2017","journal-title":"IEEE Trans. Ind. Inform."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/18\/6073\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:00:29Z","timestamp":1760166029000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/18\/6073"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9,10]]},"references-count":37,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2021,9]]}},"alternative-id":["s21186073"],"URL":"https:\/\/doi.org\/10.3390\/s21186073","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9,10]]}}}