Sensor network is the key for the network centric warfare. With the goal of providing mobile commanders with the improved situational awareness that result from a shared common operational picture, multi-sensor data fusion technologies of the battlefield become a crucial issue. In this paper, a cooperating multi-agent architecture sentinel-agent model is introduced, which provides a data fusion framework with autonomous asynchronous mobile software agents to migrate among computing nodes in a network and exploit the resources at those nodes. Then a data fusion model based on data field is introduced and analysed in detail.