{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T04:01:12Z","timestamp":1784260872702,"version":"3.55.0"},"reference-count":20,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,12]],"date-time":"2019-12-12T00:00:00Z","timestamp":1576108800000},"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>Software-Defined Networking (SDN) has opened a promising and potential approach for future networks, which mostly requires the low-level configuration to implement different controls. With the high advantages of SDN by decomposing the network control plane from the data plane, SDN has become a crucial platform to implement Internet of Things (IoT) services. However, a static SDN controller placement cannot obtain an efficient solution in distributed and dynamic IoT networks. In this paper, we investigate an optimization framework under a well-known theory, namely submodularity optimization, to formulate and address different aspects of the controller placement problem in a distributed network, specifically in an IoT scenario. Concretely, we develop a framework that deals with a series of controller placement problems from basic to complicated use cases. Corresponding to each use case, we provide discussion and a heuristic algorithm based on the submodularity concept. Finally, we present extensive simulations conducted on our framework. The simulation results show that our proposed algorithms can outperform considered baseline methods in terms of execution time, the number of controllers, and network latency.<\/jats:p>","DOI":"10.3390\/s19245474","type":"journal-article","created":{"date-parts":[[2019,12,12]],"date-time":"2019-12-12T11:06:41Z","timestamp":1576148801000},"page":"5474","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["SDN Controller Placement in IoT Networks: An Optimized Submodularity-Based Approach"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4649-8417","authenticated-orcid":false,"given":"Anh Khoa","family":"Tran","sequence":"first","affiliation":[{"name":"Modeling Evolutionary Algorithms Simulation and Artificial Intelligence, Faculty of Electrical &amp; Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3229-6785","authenticated-orcid":false,"given":"Md. Jalil","family":"Piran","sequence":"additional","affiliation":[{"name":"Computer Science and Engineering Department, Sejong University, Seoul 05006, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chuan","family":"Pham","sequence":"additional","affiliation":[{"name":"Synchromedia\u2014\u00c9cole de Technologie Sup\u00e9rieure, Universit\u00e9 du Qu\u00e9bec, QC H3C1K3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"983","DOI":"10.1109\/TLA.2016.7437249","article-title":"Network functions virtualization: A survey","volume":"14","author":"Vega","year":"2016","journal-title":"IEEE Lat. Am. Trans."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Liyanage, M., Gurtov, A., and Ylianttila, M. (2015). Software Defined Mobile Networks (SDMN): Beyond LTE Network Architecture, John Wiley & Sons.","DOI":"10.1002\/9781118900253"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1109\/LCOMM.2015.2394457","article-title":"Greco: An energy aware controller association algorithm for software defined networks","volume":"19","author":"Rivera","year":"2015","journal-title":"IEEE Commun. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1109\/MNET.2017.1600182","article-title":"The controller placement problem in software defined networking: A survey","volume":"31","author":"Wang","year":"2017","journal-title":"IEEE Network"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Varghese, B., Wang, N., Barbhuiya, S., Kilpatrick, P., and Nikolopoulos, D.S. (2016). Challenges and opportunities in edge computing. arXiv.","DOI":"10.1109\/SmartCloud.2016.18"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Heller, B., Sherwood, R., and McKeown, N. (2012, January 13). The controller placement problem. Proceedings of the First Workshop on Hot Topics in Software Defined Networks, Helsinki, Finland.","DOI":"10.1145\/2342441.2342444"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Bachem, A., Gr\u00f6tschel, M., and Korte, B. (1983). Submodular functions and convexity. Mathematical Programming The State of the Art, Springer.","DOI":"10.1007\/978-3-642-68874-4"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Beheshti, N., and Zhang, Y. (2012, January 3\u20137). Fast failover for control traffic in software-defined networks. Proceedings of the 2012 IEEE Global Communications Conference (GLOBECOM), Anaheim, CA, USA.","DOI":"10.1109\/GLOCOM.2012.6503519"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1109\/TNSM.2015.2402432","article-title":"Heuristic approaches to the controller placement problem in large scale sdn networks","volume":"12","author":"Lange","year":"2015","journal-title":"IEEE Trans. Netw. Serv. Manag."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Guo, M., and Bhattacharya, P. (2013, January 21\u201324). Controller placement for improving resilience of software-defined networks. Proceedings of the 2013 Fourth International Conference on Networking and Distributed Computing (ICNDC), Los Angeles, CA, USA.","DOI":"10.1109\/ICNDC.2013.15"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/j.comnet.2017.06.022","article-title":"Maximizing sdn control resource utilization via switch migration","volume":"126","author":"Ye","year":"2017","journal-title":"Comput. Netw."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Dixit, A., Hao, F., Mukherjee, S., Lakshman, T.V., and Kompella, R.R. (2014, January 20\u201321). Elasticon an elastic distributed SDN controller. Proceedings of the 2014 ACM\/IEEE Symposium on Architectures for Networking and Communications Systems (ANCS), Marina del Rey, CA, USA.","DOI":"10.1145\/2658260.2658261"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Qin, Q., Poularakis, K., Iosifidis, G., and Tassiulas, L. (2018, January 16\u201319). SDN controller placement at the edge: Optimizing delay and overheads. Proceedings of the IEEE INFOCOM 2018\u2014IEEE Conference on Computer Communications, Honolulu, HI, USA.","DOI":"10.1109\/INFOCOM.2018.8485963"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1108","DOI":"10.1109\/LCOMM.2016.2550026","article-title":"Optimal model for failure foresight capacitated controller placement in software-defined networks","volume":"20","author":"Killi","year":"2016","journal-title":"IEEE Commun. Lett."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Auroux, S., and Karl, H. (2015, January 9\u201312). Efficient flow processing-aware controller placement in future wireless networks. Proceedings of the 2015 IEEE Wireless Communications and Networking Conference (WCNC), New Orleans, LA, USA.","DOI":"10.1109\/WCNC.2015.7127739"},{"key":"ref_16","unstructured":"(2019, May 25). Gurobi. Available online: https:\/\/www.gurobi.com\/."},{"key":"ref_17","unstructured":"(2019, May 25). Cplex. Available online: https:\/\/www.ibm.com\/analytics\/cplex-optimizer."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1007\/BF01588971","article-title":"An analysis of approximations for maximizing submodular set functions","volume":"14","author":"Nemhauser","year":"1978","journal-title":"Math. Program."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/S0167-6377(03)00062-2","article-title":"A note on maximizing a submodular set function subject to a knapsack constraint","volume":"32","author":"Sviridenko","year":"2004","journal-title":"Oper. Res. Lett."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1080\/00107510500052444","article-title":"Power laws, pareto distributions and zipf\u2019s law","volume":"46","author":"Newman","year":"2005","journal-title":"Contemp. 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