With the advent of the Internet of Things (IoT), more and more devices can establish a connection with local area networks and use routing protocols to forward all information to the sink. But these devices may not have enough resources to execute a complex routing protocol or to memorize all information about the network. With proactive routing protocols, each node calculates the best path, and it needs enough resources to memorize the network topology.With reactive routing protocols, each node has to broadcast the message to learn the right path that the packets must follow. In all cases, in large networks such as IoT, this is not an appropriate mechanism. This paper presents a new software-defined network (SDN)-based network architecture to optimize the resource consumption of each IoT object while securing the exchange of messages between the embedded devices. In this architecture, the controller is in charge of all decisions, and objects only exchange messages and forward packets among themselves. In the case of large networks, the network is organized into clusters. Our proposed network architectures are tested with 1000 things grouped in five clusters and managed by one SDN controller. The tests using OpenDayLight and IoT embedded applications have been implemented on several scenarios providing the ability and the scalability from dynamic reorganization of the end-devices. This approach explores the network performance issues using a virtualized SDN-clustered environment which contributes to a new model for future network architectures. KEYWORDScomputer network management, distributed computing, Internet of Things, network topology, software-defined networking, wireless sensor networks INTRODUCTIONWith the Internet of Things (IoT), we have more and more devices connected to our local area network. Many of these things are only sensor devices to control humidity or the temperature of a room or to measure atmospheric pressure to predict the weather. Each of these devices is connected to the local area network of an enterprise or on the metropolitan network of a town. Sometimes, these things involve remote control as with thermostats or exchange of information between themselves as with smoke detection systems. Our goal with each thing is not only to route information on a network but also to execute orders of some kind. With the new paradigm of software-defined networking (SDN), 1,2 being one of the major research subjects obtaining support from a large number of major industries, we can decouple the control Int J Commun Syst. 2020;33:e4309.wileyonlinelibrary.com/journal/dac