The main purpose of a home automation system is to monitor and control devices from a central location. In this paper, we present the design and implementation of low-cost, flexible and secure home automation system based on SNMP standard protocol, now widely supported by device vendors for their products, such as routers, bridges and printers. Communication between SNMP agents is done on Ethernet and wireless networks. The protocol implemented between the agents is optimized to be suitable for most applications. The system is designed for low-cost and flexibility in order to reuse existing local data communication network.