The Internet of Things (IoT) and the Smart Grid both are being discussed as the technologies that would dominate Korean IT industry by 2020. The PLC, Zigbee, NFC, ANT, Wi-Fi, Bluetooth and RFID are considered to be the foundation technologies for the Smart Grid and in this paper, we propose a Zigbee-based Smart Grid Home Network System. A comparative analysis has been carried out by performing additional Mobile WiMAX-based simulations with respect to the research paper published in the conference proceedings and we confirmed that all the proposed system worked normally. Although the simulation results showed that the Mobile WiMAX has a better capability than Zigbee, the latter has more advantages in terms of scalability and the possibility of reducing the battery size as it features low-cost and low-power characteristics. As a standard technology for the low-cost and low-power oriented networks, the scalability can be achieved by its low-cost characteristic (i.e., many Zigbee equipments can be installed widely) and the size of battery can be reduced its low-power use characteristic. Considering the operating life, we’ve concluded that Zigbee could be more efficient for certain areas. The proposed foundation technology used for the system in this paper can be adapted to various areas of the IoT. Thus, in this paper, the OPNET Modeler 14.5 PL8, Zigbee-based scenario and WiMAX-based scenario had been used for the designing and simulations of both systems. We expect that it would be possible to apply the technology to a variety of fields of health-care, building and facility management, accident and disaster monitoring and meteorological observation as well.