{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T18:18:44Z","timestamp":1787854724101,"version":"build-2784847793"},"reference-count":62,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Wireless Sensor Networks (WSNs) are widely utilized in numerous applications for data collection and monitoring; however, their performance is often limited by energy constraints and the need for efficient data transmission. Network stability largely depends on node energy utilization, clustering strategy, and data transmission methods. In this work, an energy-efficient routing protocol is introduced for heterogeneous WSNs, referred to as Efficient Zonal Stable Election Routing Protocol with SOM-based node deployment (EZS-SEP). The proposed protocol aims to enhance network stability, area coverage, throughput, and overall performance by employing a hybrid communication technique and a self-organizing map (SOM) for node deployment. The WSN is divided into distinct zones based on energy levels. Normal nodes with lower energy are placed near the Base Station (BS), while intermediate and advanced nodes are positioned farther from the BS. This arrangement ensures optimal energy utilization. The Cluster Head (CH) selection mechanism of the protocol considers several critical factors, including residual energy, distance from the BS, and average node energy, ensuring that higher-energy nodes with favorable proximity are elected as CHs. Simulation results demonstrate that EZS-SEP outperforms conventional heterogeneous clustering protocols in terms of stability period, network lifetime, and throughput. Therefore, for real-world WSN applications requiring energy efficiency and reliable coverage, EZS-SEP is a suitable solution. It improves stability by 34%, 63%, 31%, and 174% compared to ESEP, P-SEP, Z-SEP, and LEACH, respectively. This study further evaluates the performance of EZS-SEP under different scenarios, including variations in BS position and initial energy levels, demonstrating its robustness across diverse network conditions.<\/jats:p>","DOI":"10.1371\/journal.pone.0346479","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T17:27:11Z","timestamp":1787851631000},"page":"e0346479","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["EZS-SEP: A hybrid efficient zonal stable election routing protocol with SOM-based node deployment for heterogeneous wireless sensor networks"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-7999-7822","authenticated-orcid":true,"given":"Sumit","family":"Das","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-1671-5290","authenticated-orcid":true,"given":"Md. 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SEP: A stable election protocol for clustered heterogeneous wireless sensor networks. In: Second Int. Workshop Sens. Actor Netw. Protoc. Appl. SANPA 2004. 2004."},{"issue":"6","key":"pone.0346479.ref018","doi-asserted-by":"crossref","first-page":"1424","DOI":"10.1109\/TSP.2014.2302746","article-title":"Distributed Maximum Likelihood Sensor Network Localization","volume":"62","author":"A Simonetto","year":"2014","journal-title":"IEEE Trans Signal Process"},{"key":"pone.0346479.ref019","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1145\/375735.376399","article-title":"Distributed sensor network for real time tracking","author":"B Horling","year":"2001","journal-title":"Proceedings of the fifth international conference on Autonomous agents"},{"key":"pone.0346479.ref020","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0925-2312(98)00030-7","article-title":"The self-organizing map","volume":"21","author":"T Kohonen","year":"1998","journal-title":"Neurocomputing"},{"key":"pone.0346479.ref021","first-page":"1","author":"N Hoang","year":"2023"},{"key":"pone.0346479.ref022","first-page":"268","year":"2021"},{"key":"pone.0346479.ref023","author":"S Faisal","year":"2013"},{"key":"pone.0346479.ref024","first-page":"368","author":"MJ Handy"},{"issue":"9","key":"pone.0346479.ref025","doi-asserted-by":"crossref","first-page":"1396","DOI":"10.1109\/LCOMM.2012.073112.120450","article-title":"Distance Based Thresholds for Cluster Head Selection in Wireless Sensor Networks","volume":"16","author":"SH Kang","year":"2012","journal-title":"IEEE Commun Lett"},{"key":"pone.0346479.ref026","article-title":"Research on Improved LEACH Protocol of Wireless Sensor Networks","author":"J Shan","year":"2013","journal-title":"Przegl\u0105d Elektrotechniczny"},{"issue":"4","key":"pone.0346479.ref027","doi-asserted-by":"crossref","first-page":"366","DOI":"10.1109\/TMC.2004.41","article-title":"HEED: a hybrid, energy-efficient, distributed clustering approach for ad hoc sensor networks","volume":"3","author":"O Younis","year":"2004","journal-title":"IEEE Transactions on Mobile Computing"},{"key":"pone.0346479.ref028","first-page":"909","author":"MdS Ali","year":"2008"},{"issue":"4","key":"pone.0346479.ref029","doi-asserted-by":"crossref","first-page":"985","DOI":"10.26599\/TST.2023.9010056","article-title":"Efficient Communication in Wireless Sensor Networks Using Optimized Energy Efficient Engroove Leach Clustering Protocol","volume":"29","author":"N Meenakshi","year":"2024","journal-title":"Tsinghua Sci Technol"},{"key":"pone.0346479.ref030","first-page":"3","author":"S Lindsey","year":"2002"},{"key":"pone.0346479.ref031","first-page":"2230","author":"S Feng","year":"2011"},{"key":"pone.0346479.ref032","author":"MR Jafri","year":"2013"},{"key":"pone.0346479.ref033","article-title":"Distance-Distributed Energy Efficient Clustering (D-DEEC) Routing Protocol for Wireless Sensor Network","author":"F Jibreel","journal-title":"Asian J Research in Computer Science"},{"issue":"16","key":"pone.0346479.ref034","doi-asserted-by":"crossref","first-page":"9","DOI":"10.5120\/9364-3804","article-title":"Distance-based stable election protocol (DB-SEP) for heterogeneous wireless sensor network","volume":"58","author":"S Benkirane","year":"2012","journal-title":"International J Computer Applications"},{"key":"pone.0346479.ref035","first-page":"373","author":"AA Khan","year":"2012"},{"issue":"16","key":"pone.0346479.ref036","first-page":"35","article-title":"Modified stable election protocol (M-SEP) for hierarchical WSN","volume":"79","author":"G Arya","year":"2013","journal-title":"Int J Comput Appl"},{"key":"pone.0346479.ref037","first-page":"1","author":"AA Malluh","year":"2014"},{"key":"pone.0346479.ref038","doi-asserted-by":"crossref","first-page":"55726","DOI":"10.1109\/ACCESS.2022.3177190","article-title":"DE-SEP: Distance and Energy Aware Stable Election Routing Protocol for Heterogeneous Wireless Sensor Network","volume":"10","author":"A 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Networks","volume":"22","author":"N Kumar","year":"2022","journal-title":"IEEE Sensors J"},{"issue":"4","key":"pone.0346479.ref049","doi-asserted-by":"crossref","first-page":"2643","DOI":"10.1007\/s11277-015-2925-x","article-title":"Enhanced Threshold Sensitive Stable Election Protocol for Heterogeneous Wireless Sensor Network","volume":"85","author":"S Kumar","year":"2015","journal-title":"Wireless Personal Communications"},{"key":"pone.0346479.ref050","first-page":"101","article-title":"Distance Based Enhanced Threshold Sensitive Stable Election Routing Protocol for Heterogeneous Wireless Sensor Network.","author":"R Rani","year":"2019","journal-title":"Computational Intelligence in Sensor Networks. Berlin, Heidelberg: Springer"},{"key":"pone.0346479.ref051","doi-asserted-by":"crossref","first-page":"01075","DOI":"10.1051\/e3sconf\/202129701075","article-title":"Three level heterogeneous zonal stable election protocol for energy efficiency in wireless sensor networks","volume":"297","author":"A Benelhouri","year":"2021","journal-title":"E3S Web Conf"},{"issue":"4","key":"pone.0346479.ref052","doi-asserted-by":"crossref","DOI":"10.3390\/s21041021","article-title":"EZ-SEP: Extended Z-SEP Routing Protocol with Hierarchical Clustering Approach for Wireless Heterogeneous Sensor Network","volume":"21","author":"Z Nurlan","year":"2021","journal-title":"Sensors"},{"key":"pone.0346479.ref053","doi-asserted-by":"crossref","first-page":"100048","DOI":"10.1016\/j.prime.2022.100048","article-title":"Improved Zonal Stable Election Protocol (IZ-SEP) for hierarchical clustering in heterogeneous wireless sensor networks","volume":"2","author":"MdK Alom","year":"2022","journal-title":"e-Prime - Advances in Electrical Engineering, Electronics and Energy"},{"issue":"3","key":"pone.0346479.ref054","doi-asserted-by":"crossref","first-page":"2756","DOI":"10.1109\/TVT.2021.3058282","article-title":"Reinforcement Learning-Based Opportunistic Routing Protocol for Underwater Acoustic Sensor Networks","volume":"70","author":"Y Zhang","year":"2021","journal-title":"IEEE Trans Veh Technol"},{"key":"pone.0346479.ref055","author":"P Soltani","year":"2025"},{"issue":"3","key":"pone.0346479.ref056","doi-asserted-by":"crossref","first-page":"1685","DOI":"10.1007\/s12083-022-01315-6","article-title":"Reinforcement-Learning based energy efficient optimized routing protocol for WSN","volume":"15","author":"A Keerthika","year":"2022","journal-title":"Peer-to-Peer Netw Appl"},{"issue":"15","key":"pone.0346479.ref057","doi-asserted-by":"crossref","first-page":"30047","DOI":"10.1109\/JSEN.2025.3582381","article-title":"Hybrid Energy-Efficient Clustering With Reinforcement Learning for IoT-WSNs Using Knapsack and K -Means","volume":"25","author":"A Aleem","year":"2025","journal-title":"IEEE Sensors J"},{"issue":"1","key":"pone.0346479.ref058","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1109\/TSMCA.2004.838486","article-title":"Energy-Efficient Deployment of Intelligent Mobile Sensor Networks","volume":"35","author":"N Heo","year":"2005","journal-title":"IEEE Trans Syst, Man, Cybern A"},{"key":"pone.0346479.ref059","unstructured":"Sadeghi Ghahroudi M, Shahrabi A, Boutaleb T. An efficient self-organizing node deployment algorithm for mobile sensor networks: The Twelfth International Conference on Mobile Ubiquitous Computing, Systems, Services and Technologies. In: UBICOMM 2018 Twelfth Int. Conf. Mob. Ubiquitous Comput. Syst. Serv. Technol. 2018. 89\u201394."},{"key":"pone.0346479.ref060","first-page":"1113","author":"L Paladina","year":"2007"},{"issue":"16","key":"pone.0346479.ref061","doi-asserted-by":"crossref","DOI":"10.1002\/dac.5309","article-title":"A distributed self\u2010organising node deployment algorithm for mobile sensor networks","volume":"35","author":"M Sadeghi Ghahroudi","year":"2022","journal-title":"Int J Communication"},{"key":"pone.0346479.ref062","doi-asserted-by":"crossref","first-page":"1869","DOI":"10.1007\/s11276-018-1877-y","article-title":"An information entropy based-clustering algorithm for heterogeneous wireless sensor networks,","author":"W Osamy","year":"2020","journal-title":"Wirel. 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