Also there are many operating system is being developed for IoT. Linux is used for IoT such as Raspberry pi uses Debian Linux. RTOS also is used for IoT because some IoT devices should be work in real time. A message transmission is one of main key factor of IoT software. A message transmission system sends the data which are collected from hardware device to a server or a user. Also it should receive data or a command from a server or a user. IoT device is designed for working alone without human decision so exact messages delivery is highly important. It could happen accident if there is a message missing or a wrong message delivery. People would like to use sensor devices such as smoke detectors, gas and water leakage detectors in home automation [8] and it is highly important that deliver sensor data exact once in order. Therefore, research of reliable message delivery and development are being going continuously.