Advance in hardware technology and engineering design have led to dramatic reduction in size, power consumption and cost for digital circuiting, wireless communication and micro electro mechanics sensors (MEMS). This has enabled very compact, autonomous and mobile nodes each containing of one or more sensors. This millimeter scale nodes each called as SMARTDUST. It was discovered at Berkeley at University of California by a team led by Prof.Kristofer.S.J. Pister This device is around size of grain of sand and contains sensors, computing ability, bi-directional wireless communication and a power supply.As tiny as dust particles, smart dust motes can be spread throughout buildings or into the atmosphere to collect and monitor data. Thus smart dust as small as a grain of rice is able to sense, think, talk and listen. Smart dust devices have applications in everything from military to meteorological to medical fields.