Innovative idea of  smart cities  gained much significance as it facilitates the economic growth  and increase in GDP. Development in ICT (Information and Communication Technology) is key role player in  smart city concept.It is backbone of smart city environment. Basically it is considered as integrated systems and many life aspects are linked together to get the improved life style. Main domains integrated in the ‘Smartcity’ system are power, transportation, buildings, public securities, waste and water management ,city governance and health care. Smart city applications provide quality of life solutions related to these domains. Smart city applications  basically involve pervasive and ubiquitous environment and  Internet of Things can make it possible. Continuously sensing and actuating components produce the large amount of speedy ,real time data And hence this ecosystem comes under “BIGDATA”  ecosystem.