Internet of Things (IoT) comprises physical devices with an IP address equipped with wireless sensors and/or wireless communication devices. Due to the increase in the number of devices and data production, it is difficult to create manageable, intelligent networks. Models have been proposed to solve existing problems and improve network performance. However, traditional network technology is not capable of solving problems caused by such a large number of devices and the large data transmission it generates. Software Defined Networking (SDN) provides opportunities for innovation in network control, management and network programmability by separating the control layer from the data layer in computer networks. SDN is used in IoT networks to improve network performance, provide more direct control over routing, analyze network traffic and manage the network effectively with the centralized controller. In this study, an architecture is proposed for efficient transmission of sensor data in SDN based IoT networks. In the model simulated with Mininet and POX controller, average packet loss and delay are calculated for varying numbers of switches and path hop counts. It was found that the number of hops had significant impact on delay and loss rate, while the total number of switches in the network had no linear relationship with hop counts.