Sensor nodes have been always acting only as a data collector inside wireless sensor networks. They usually perform energy-aware routing independently from the properties of collected sensed data. Such sensed data is interpreted into useful context information at the gateway after a great time lag and the sensors cannot respond to sudden events very rapidly. In this paper, we introduce the In-network Semantic Sensor Data Model (IS_SDM) which can provide sensor nodes with context-awareness and also energy consumption consideration. Sensor nodes can be more intelligent in adapting to ambient changes while data collection can be achieved more efficiently.